problems inserting finish page

my script is as follows

; declare variables
Var PalmUserList ; Used to dynamically populate dropdown on User Selection page
Var UserChoice ; Selected Palm Username
Var InstallStatus ; Defined when the installer is aborting
Var SurveyName ; Survey full path from command line parameter
Var StatPDB ; full path of EpiSurveyor_stat.pdb
Var PublishDir
Var count
Var isSelectAll
Var userLists
Var UserSelection
Var HWND
Var ChildSurveyName
Var Survey
Name "Survey Publisher" ;Display name for installer

; declare macros
!macro IndexOf Var Str Char
Push "${Char}"
Push "${Str}"
Call IndexOf
Pop "${Var}"
!macroend
!define IndexOf "!insertmacro IndexOf"

!macro StrRep ResultVar String SubString RepString
Push "${String}"
Push "${SubString}"
Push "${RepString}"
Call StrRep
Pop "${ResultVar}"
!macroend
!define StrRep "!insertmacro StrRep"

!include "MUI.nsh"
!include "LogicLib.nsh"
!include "WinMessages.nsh"

;--------------------------------
;Configuration
; Name of the resulting executable installer file
OutFile "publish.exe"

; I don't intend to install any files permenantly on the PC, so
; use the system temporary directory
InstallDir "$TEMP\EpiSurveyorSetup"
;--------------------------------
;Modern UI Configuration

; Show a license agreement page
!define MUI_LICENSEPAGE
; Show a warning when the user cancels the install
!define MUI_ABORTWARNING
; I'm using some custom pages
!define MUI_CUSTOMPAGECOMMANDS
; Show a finish page at the end of the installation
!define MUI_FINISHPAGE
; Don't present the option to reboot the computer on the finish page
!define MUI_FINISHPAGE_NOREBOOTSUPPORT
; The icon for the installer title bar and .exe file
;!define MUI_ICON "eclipse.ico"
; I've written a function that I want to be called when the user cancels the installation
!define MUI_CUSTOMFUNCTION_ABORT myOnAbort
; Override the text on the Finish Page
!define MUI_FINISHPAGE_TITLE "Installation Complete"
!define MUI_FINISHPAGE_TEXT "Survey has been queued for installation on the selected Palm devices.\r\n\r\nClick 'Finish,' then HotSync each device to complete publishing."

;--------------------------------
; Modern UI Pages (listed in order they will appearance
; file installation page (preps needed files)
!insertmacro MUI_PAGE_INSTFILES
; custom page for choosing the Palm user(s) to publish to
Page custom ShowUserList LeaveCustom
!define MUI_WELCOMEFINISHPAGE_CUSTOMFUNCTION_INIT DisableBackButton
; this will be called before the finish page is displayed to perform cleanup
!define MUI_PAGE_CUSTOMFUNCTION_PRE myFinishPre
!insertmacro MUI_PAGE_FINISH

;--------------------------------
;Languages
; English only for now
!insertmacro MUI_LANGUAGE "English"

;--------------------------------
;Language Strings
;Description text that I want to appear while files are being copied
LangString DESC_SecCopyUI ${LANG_ENGLISH} "Copying the Palm files to your computer so they can be installed to your device."
;Header text for all pages in the installer
LangString TEXT_IO_TITLE ${LANG_ENGLISH} "EpiSurveyor"
LangString TEXT_IO_SUBTITLE ${LANG_ENGLISH} "Publish a survey to your devices"

;--------------------------------
;Reserve Files

;Things that need to be extracted first (keep these lines before any File command!)
;Required for proper behavior when using BZIP2 compression
ReserveFile "showUserList.ini"
!insertmacro MUI_RESERVEFILE_INSTALLOPTIONS

;--------------------------------
;Installer Sections

Section "Prep for install" SecCopyUI
; get survey name from command line parameter
Push $R0
Call GetParameters
Pop $R0
${StrRep} $R0 $R0 "/" "\" ; replace slashes
StrCpy $SurveyName $R0
Loop:
; loop until we have the index of the last slash
${IndexOf} $R1 $R0 "\"
IntOp $0 $R1 + 1 ;advance index past the slash
StrCpy $R0 $R0 "" $0 ; $R0 now has first segment of path removed
StrCmp $R1 -1 LastToken Next
Next:
IntOp $R2 $R2 + $R1 ; sum of segments we've traversed found so far
IntOp $R2 $R2 + 1 ; add one for the slash
GoTo Loop
LastToken:
IntOp $3 $3 + 1
StrCpy $Survey $R0
; MessageBox MB_OK|MB_ICONINFORMATION "index = $R2"
StrLen $1 $SurveyName
; MessageBox MB_OK|MB_ICONINFORMATION "path length = $1"
IntOp $2 $R2 - $1 ; index minux length of string: negative to count back from end of string
;MessageBox MB_OK|MB_ICONINFORMATION "length of shortened path = $2"
StrCpy $R3 $SurveyName $2
; MessageBox MB_OK|MB_ICONINFORMATION "value of R3 IS $R3"
StrCpy $PublishDir $R3
;MessageBox MB_OK|MB_ICONINFORMATION "publish dir is $PublishDir"
StrCpy $StatPDB "$R3EpiSurveyor_stat.pdb"
SetOutPath "$INSTDIR"
; Copy the files that we will use
File "UserData.dll"
File "InstAide.dll"

SectionEnd

;--------------------------------
;Descriptions

!insertmacro MUI_FUNCTION_DESCRIPTION_BEGIN
!insertmacro MUI_DESCRIPTION_TEXT ${SecCopyUI} $(DESC_SecCopyUI)
!insertmacro MUI_FUNCTION_DESCRIPTION_END

;--------------------------------
;Installer Functions

Function .onInit

;Extract InstallOptions INI Files
!insertmacro MUI_INSTALLOPTIONS_EXTRACT_AS "showUserList.ini" "showUserList.ini"
!insertmacro MUI_INSTALLOPTIONS_EXTRACT "showUserList.ini"
!insertmacro MUI_INSTALLOPTIONS_EXTRACT "installfiles.ini"
FunctionEnd

; displays our custom "Select Palm User" page
Function ShowUserList

Call GetPalmUserList
; Use this list to populate the list on our custom page
!insertmacro MUI_INSTALLOPTIONS_WRITE "showUserList.ini" "Field 2" "ListItems" "$PalmUserList"
!insertmacro MUI_HEADER_TEXT "$(TEXT_IO_TITLE)" "$(TEXT_IO_SUBTITLE)"
!insertmacro MUI_INSTALLOPTIONS_INITDIALOG "showUserList.ini"
Pop $HWND
GetDlgItem $1 $HWNDPARENT 1
EnableWindow $1 0

!insertmacro MUI_INSTALLOPTIONS_SHOW
Pop $0
InstallOptions::initDialog /NOUNLOAD "$PLUGINSDIR\showUserList.ini"
Call LeaveCustom
; if we are aborting, do not check the value of UserChoice (if we do, then
; if the user cancels the install without selecting a user, it will insist
; that the user choose a user before exiting)
StrCmp $InstallStatus "aborting_ir_install" End 0
!insertmacro MUI_INSTALLOPTIONS_READ $UserChoice "showUserList.ini" "Field 2" "State"
StrCmp $isSelectAll "1" End
StrCmp $isSelectAll "0" End
; Verify that the user chose a valid user. If not, display the ShowUserList
; screen again.
; Why not simply set MinLen of the dropdown to 1? This will prevent the user
; from continuing without selecting a user, but it will not present any
; messagebox or other dialog. That is confusing to the user!
StrCmp $UserChoice "" 0 Continue
MessageBox MB_OK|MB_ICONINFORMATION "You must choose at least one user to proceed."
Call ShowUserList
GoTo End
Continue:
; MessageBox MB_OK|MB_ICONINFORMATION "About to call InstallFiles function."
Call InstallFiles
; MessageBox MB_OK|MB_ICONINFORMATION "Just returned from InstallFiles function."
End:
FunctionEnd

Function LeaveCustom
; At this point the user has either pressed Next or one of our custom buttons
; We find out which by reading from the INI file
ReadINIStr $0 "$PLUGINSDIR\showUserList.ini" "Settings" "State"
!insertmacro MUI_INSTALLOPTIONS_READ $UserSelection "showUserList.ini" "Field 2" "State"
StrCmp $0 0 Done ; Next button?
StrCmp $0 3 SelectAll ; select all users
StrCmp $0 4 UnselectAll ; unselect all users
;added by shwetha on dec 07,2007
StrCmp $0 2 Selection
Abort ; Return to the page

SelectAll:
StrCpy $isSelectAll "1"
GetDlgItem $1 $HWNDPARENT 1
EnableWindow $1 1
GetDlgItem $1 $HWND 1203
EnableWindow $1 1
;added on dec 04,2007
GetDlgItem $1 $HWND 1202
EnableWindow $1 0
GetDlgItem $1 $HWND 1201
SendMessage $1 ${LB_SELITEMRANGEEX} 0 $count
StrCpy $userLists $PalmUserList
Abort

UnselectAll:
GetDlgItem $0 $HWND 1201
SendMessage $1 ${LB_SETSEL} 0 -1
GetDlgItem $1 $HWNDPARENT 1
EnableWindow $1 0
StrCpy $isSelectAll "0"
GetDlgItem $1 $HWND 1203
EnableWindow $1 0
;added on dec 04,2007
GetDlgItem $1 $HWND 1202
EnableWindow $1 1
StrCpy $userLists ""
Abort

Selection:
!insertmacro MUI_INSTALLOPTIONS_READ $UserSelection "showUserList.ini" "Field 2" "State"
StrCmp $UserSelection "" Disable
Disable:
GetDlgItem $1 $HWNDPARENT 1
EnableWindow $1 0
StrCmp $UserSelection "" End Cont
Cont:
GetDlgItem $1 $HWNDPARENT 1
EnableWindow $1 1
call InstallFiles
End:
Abort

Done:
StrCmp $isSelectAll 1 installAll
StrCmp $isSelectAll 0 next
StrCmp $UserChoice "" msg ; check if no users have been selected
installAll:
call InstallAllFiles
StrCpy $userLists ""
StrCmp $userLists "" msg
Abort
next:
StrCmp $UserChoice "" msg
StrCmp $isSelectAll "" msg
StrCmp $UserSelection "" msg
msg:
FunctionEnd

Function InstallAllFiles
; MessageBox MB_OK|MB_ICONINFORMATION "Installing for all the users in progress...."
; ==================== INSTALL PRC/PDB FILES ==========================
; Set the PRC file to be installed to internal memory on next HotSync
StrCpy $1 $UserChoice
StrCpy $UserChoice $userLists ;
Loop:
${IndexOf} $R0 $UserChoice "|"
StrCpy $R3 $R0 ; if this was the last token $R3 will be -1 and we'll stop looping
StrCmp $R3 -1 LastToken Moveon
LastToken:
StrCpy $1 $UserChoice
Goto InstallSurveyPDB
Moveon:
StrCpy $1 $UserChoice $R0 ; $1 = first token
IntOp $R0 $R0 + 1
StrCpy $R2 $UserChoice "" $R0 ; R2 = new $UserChoice
StrCpy $UserChoice $R2

InstallSurveyPDB:
StrCpy $2 "$SurveyName.pdb"
;MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "Attempting install of $2 for user $1 PltInstallFile returned value of $3"
StrCmp $3 "-504" +1 +3 ;ERR_PILOT_COPY_FAILED
; MessageBox MB_OK|MB_ICONINFORMATION "Copy Failed"
Goto InstallOtherPDBs
StrCmp $3 "-512" +1 InstallOtherPDBs ;ERR_PILOT_FILE_ALREADY_EXISTS
;MessageBox MB_OK|MB_ICONINFORMATION "Uninstalling $2 for user $1"
System::Call 'InstAide::PltRemoveInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltRemoveInstallFile returned value of $3"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"

InstallOtherPDBs:
StrCpy $2 "$StatPDB"
;MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
; MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"
; We don't care if there is one of these in the queue already, it'll do fine

StrCpy $2 "$SurveyName_data.pdb"
; MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"
; We don't care if there is one of these in the queue already, it'll do fine
Strcmp $count 0 End increment

increment:
IntOp $count $count - 1
Strcmp $count 0 End Loop
StrCmp $R3 -1 End Loop
; StrCpy $userLists ""
End:
; ==================== SHOW CUSTOM PAGE ==========================
; !insertmacro MUI_HEADER_TEXT "$(TEXT_IO_TITLE)" "$(TEXT_IO_SUBTITLE)"
;!insertmacro MUI_INSTALLOPTIONS_DISPLAY "installfiles.ini"

FunctionEnd

Function InstallFiles

; ==================== INSTALL PRC/PDB FILES ==========================
; Set the PRC file to be installed to internal memory on next HotSync
StrCpy $1 $UserChoice

StrCpy $UserSelection "$UserSelection|"
Loop:
${IndexOf} $R0 $UserSelection "|"
StrCpy $R3 $R0 ; if this was the last token $R3 will be -1 and we'll stop looping
StrCmp $R3 -1 LastToken Moveon
LastToken:
StrCpy $1 $UserSelection
Goto InstallSurveyPDB
Moveon:
StrCpy $1 $UserSelection $R0
; MessageBox MB_OK|MB_ICONINFORMATION "first user is $1"
IntOp $R0 $R0 + 1
;StrCpy $R2 $UserChoice "" $R0 ; R2 = new $UserChoice
StrCpy $R2 $UserSelection "" $R0 ; R2 = new $UserChoice
;MessageBox MB_OK|MB_ICONINFORMATION "next user is $R2"
StrCpy $UserSelection $R2

InstallSurveyPDB:
; MessageBox MB_OK|MB_ICONINFORMATION " inside InstallSurveyPDB"
StrCpy $2 "$SurveyName.pdb"
;MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "Attempting install of $2 for user $1 PltInstallFile returned value of $3"
StrCmp $3 "-504" +1 +3 ;ERR_PILOT_COPY_FAILED
;MessageBox MB_OK|MB_ICONINFORMATION "Copy Failed"
Goto InstallOtherPDBs
StrCmp $3 "-512" +1 InstallOtherPDBs ;ERR_PILOT_FILE_ALREADY_EXISTS
; MessageBox MB_OK|MB_ICONINFORMATION "Uninstalling $2 for user $1"
System::Call 'InstAide::PltRemoveInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltRemoveInstallFile returned value of $3"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"

InstallOtherPDBs:
;MessageBox MB_OK|MB_ICONINFORMATION " inside InstallotherPDB"
StrCpy $2 "$StatPDB"
; MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"
; We don't care if there is one of these in the queue already, it'll do fine

StrCpy $2 "$SurveyName_data.pdb"
;MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltInstallFile(t r1, t r2) i .r3'
; MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"
; We don't care if there is one of these in the queue already, it'll do fine

StrCmp $R3 -1 AbortLoop Loop
AbortLoop:
; ==================== SHOW CUSTOM PAGE ==========================
;!insertmacro MUI_HEADER_TEXT "$(TEXT_IO_TITLE)" "$(TEXT_IO_SUBTITLE)"
;!insertmacro MUI_INSTALLOPTIONS_DISPLAY "installfiles.ini"
FunctionEnd

Function GetPalmUserList
; NSIS has to be using the directory containing the dll for it to find it
SetOutPath "$INSTDIR"
File "UserData.dll" ; copy dll there
System::Call 'UserData::UmGetUserCount(v) i .r1'
;MessageBox MB_OK|MB_ICONINFORMATION "There seem to be $1 Palm users"
;added byy shwetha for retreiving the palm users count
StrCpy $count $1
;added by shwetha ends here
IntCmp $1 0 0 0 foundInstaller ; if return value of PltGetUserCount is 0 or negative, then we can't continue
MessageBox MB_OK|MB_ICONINFORMATION "No Palm Installer was found on your system. The installation cannot complete. Please ensure that the latest version of the Palm Desktop Software is installed on your computer before installing."
Abort
foundInstaller:

; Compile the list of Palm Users
StrCpy $2 0 ; Initialize counter
StrCpy $PalmUserList "" ; Initialize list
Loop:
StrCpy $4 ${NSIS_MAX_STRLEN} ; $4 will tell the function the buffer length of $3
; $3 will be set to the username of the user indexed by $2
System::Call 'UserData::UmGetUserID(i r2, *i r6r6) i .r5'
System::Call 'UserData::UmGetUserName(i r6, t .r3, *i r4) i .r5'
;MessageBox MB_OK|MB_ICONINFORMATION "User indexed at $2 has ID $6 and name $3"
StrCpy $PalmUserList "$PalmUserList$3|"
IntOp $2 $2 + 1 ; Incriment the counter
IntCmp $2 $1 0 Loop 0

FunctionEnd

Function RemoveFiles
; We need to Unload the dll so that it can be deleted
System::Call 'InstAide::PltGetUserCount(v) i .r1 ?u'
System::Call 'UserData::UmGetUserCount(v) i .r1 ?u'
; I read somewhere that you should do this. Don't know what it does
SetPluginUnload manual
System::Free 0
; Remove all of the files
SetOutPath $TEMP
Delete "$INSTDIR\InstAide.dll"
Delete "$INSTDIR\UserData.dll"
SetOutPath $PublishDir
Delete "$SurveyName.pdb"
Delete "$SurveyName_data.pdb"
Delete "$StatPDB"
RMDir /r "$INSTDIR"
FunctionEnd

Function RemoveInstallFiles
; Un-schedule the files for installation to internal memory

StrCpy $1 $UserChoice ; pipe-delimited string containing usernames

Loop:
; Search string for pipe to get a token
${IndexOf} $R0 $UserChoice "|"
StrCpy $R3 $R0 ; if this was the last token $R3 will be -1 and we'll stop looping
StrCmp $R3 -1 LastToken Moveon
LastToken:
StrCpy $1 $UserChoice
Goto UnInstall
Moveon:
StrCpy $1 $UserChoice $R0 ; $1 = first token
IntOp $R0 $R0 + 1
StrCpy $R2 $UserChoice "" $R0 ; R2 = new $UserChoice
StrCpy $UserChoice $R2

UnInstall:
StrCpy $2 "$SurveyName.pdb"
;MessageBox MB_OK|MB_ICONINFORMATION "Uninstalling $2 for user $1"
System::Call 'InstAide::PltRemoveInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"

StrCpy $2 "$SurveyName_data.pdb"
;MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltRemoveInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"

StrCpy $2 "$StatPDB"
;MessageBox MB_OK|MB_ICONINFORMATION "Installing $2 for user $1"
System::Call 'InstAide::PltRemoveInstallFile(t r1, t r2) i .r3'
;MessageBox MB_OK|MB_ICONINFORMATION "PltInstallFile returned value of $3"

StrCmp $R3 -1 Continue Loop
Continue:
FunctionEnd

Function DisableBackButton
GetDlgItem $1 $HWNDPARENT 3
EnableWindow $1 0
FunctionEnd

Function myFinishPre
;MessageBox MB_OK|MB_ICONINFORMATION "myFinishPre about to remove files"
; Before we exit the installer, clean up all of the files that we copied
; to the PC
MessageBox MB_OK|MB_ICONINFORMATION "installation completed for $Survey"
Call RemoveFiles
FunctionEnd

Function myOnAbort
;MessageBox MB_OK|MB_ICONINFORMATION "WE ARE ABORTING !!!"
; Let other parts of the installer know that we are aborting
StrCpy $InstallStatus "aborting_ir_install"
; In case we've already scheduled files for installation on the next HotSync,
; we should un-schedule them
Call RemoveInstallFiles
; Clean up all of the files that we copied to the PC
Call RemoveFiles
FunctionEnd

Function IndexOf
Exch $R0
Exch
Exch $R1
Push $R2
Push $R3

StrCpy $R3 $R0
StrCpy $R0 -1
IntOp $R0 $R0 + 1
StrCpy $R2 $R3 1 $R0
StrCmp $R2 "" +2
StrCmp $R2 $R1 +2 -3

StrCpy $R0 -1

Pop $R3
Pop $R2
Pop $R1
Exch $R0
FunctionEnd

; GetParameters
; input, none
; output, top of stack (replaces, with e.g. whatever)
; modifies no other variables.

Function GetParameters

Push $R0
; MessageBox MB_OK|MB_ICONINFORMATION "survey $R0"
Push $R1
Push $R2
Push $R3

StrCpy $R2 1
StrLen $R3 $CMDLINE
;Check for quote or space
StrCpy $R0 $CMDLINE $R2
StrCmp $R0 '"' 0 +3
StrCpy $R1 '"'
Goto loop
StrCpy $R1 " "

loop:
IntOp $R2 $R2 + 1
StrCpy $R0 $CMDLINE 1 $R2
StrCmp $R0 $R1 get
StrCmp $R2 $R3 get
Goto loop

get:
IntOp $R2 $R2 + 1
StrCpy $R0 $CMDLINE 1 $R2
StrCmp $R0 " " get
StrCpy $R0 $CMDLINE "" $R2

Pop $R3
Pop $R2
Pop $R1
Exch $R0
;MessageBox MB_OK|MB_ICONINFORMATION "survey $R0"
FunctionEnd

Function StrRep
/*After this point:
------------------------------------------
$R0 = RepString (input)
$R1 = SubString (input)
$R2 = String (input)
$R3 = RepStrLen (temp)
$R4 = SubStrLen (temp)
$R5 = StrLen (temp)
$R6 = StartCharPos (temp)
$R7 = TempStrL (temp)
$R8 = TempStrR (temp)*/

;Get input from user
Exch $R0
Exch
Exch $R1
Exch
Exch 2
Exch $R2
Push $R3
Push $R4
Push $R5
Push $R6
Push $R7
Push $R8

;Return "String" if "SubString" is ""
${IfThen} $R1 == "" ${|} Goto Done ${|}

;Get "RepString", "String" and "SubString" length
StrLen $R3 $R0
StrLen $R4 $R1
StrLen $R5 $R2
;Start "StartCharPos" counter
StrCpy $R6 0

;Loop until "SubString" is found or "String" reaches its end
${Do}
;Remove everything before and after the searched part ("TempStrL")
StrCpy $R7 $R2 $R4 $R6

;Compare "TempStrL" with "SubString"
${If} $R7 == $R1
;Split "String" to replace the string wanted
StrCpy $R7 $R2 $R6 ;TempStrL

;Calc: "StartCharPos" + "SubStrLen" = EndCharPos
IntOp $R8 $R6 + $R4

StrCpy $R8 $R2 "" $R8 ;TempStrR

;Insert the new string between the two separated parts of "String"
StrCpy $R2 $R7$R0$R8
;Now calculate the new "StrLen" and "StartCharPos"
StrLen $R5 $R2
IntOp $R6 $R6 + $R3
${Continue}
${EndIf}

;If not "SubString", this could be "String" end
${IfThen} $R6 >= $R5 ${|} ${ExitDo} ${|}
;If not, continue the loop
IntOp $R6 $R6 + 1
${Loop}

Done:

;Return output to user
StrCpy $R0 $R2

/*After this point:
------------------------------------------
$R0 = ResultVar (output)*/

Pop $R8
Pop $R7
Pop $R6
Pop $R5
Pop $R4
Pop $R3
Pop $R2
Pop $R1
Exch $R0
FunctionEnd