7-zip 4.40 now can open nsis exe file

but the .nsi file that are diff from the orignal

the orignal
;Names
Name "Sarp2000"
Caption "Sarp2000 3.0 °²×°"

!include "MUI.nsh"
!include "Sections.nsh"
;--------------------------------
;Configuration

;General
OutFile "sarp${__DATE__}.exe"

SetCompressor /SOLID lzma ;LT 20050802SetCompressor lzma ;LT ADD 20031219
;Folder selection page
;InstallDir "$PROGRAMFILES\${MUI_PRODUCT}"
InstallDir $PROGRAMFILES\Sarp2002
InstallDirRegKey HKLM SOFTWARE\Sarp2002 "Install_Dir"
!packhdr tmp.dat "upx -9 -q tmp.dat"
!system "upx -9 -q sarp.exe" 0

;--------------------------------
;Modern UI Configuration

!define MUI_WELCOMEPAGE
!define MUI_LICENSEPAGE
!define MUI_COMPONENTSPAGE
!define MUI_DIRECTORYPAGE
!define MUI_FINISHPAGE
!define MUI_FINISHPAGE_RUN "$INSTDIR\sarp.exe"

!define MUI_ABORTWARNING

!define MUI_UNINSTALLER
!define MUI_UNCONFIRMPAGE

;!define MUI_UI "${NSISDIR}\Contrib\UIs\modern2.exe"
;The interface file with the dialog resources.

----------------------------
the file extract
WriteINIStr 44 53 63 65
WriteINIStr 44 83 0 65
WriteINIStr 44 98 0 65
WriteINIStr 112 93 -37 65
WriteINIStr 112 120 127 65
WriteINIStr 130 138 142 65
WriteINIStr 130 120 145 65
WriteINIStr 130 93 -38 65
GetFunctionAddress 0 0
GetDlgItem 30 149 153
ShowWindow 158 162
GetDlgItem 30 149 164
ShowWindow 158 162
GetDlgItem 30 149 169
ShowWindow 158 162
GetDlgItem 30 149 174
ShowWindow 158 162
GetDlgItem 30 149 179
ShowWindow 158 162
GetDlgItem 30 149 184
ShowWindow 158 162
GetDlgItem 30 149 189
ShowWindow 158 194
GetFunctionAddress 1 0
Call 289
File $PLUGINSDIR\InstallOptions.dll
UpdateSatusText 8
Push $PLUGINSDIR\ioSpecial.ini

There is already a topic open on this subject (two, actually). Please use this thread to post here.

It is impossible to completely decompile an NSIS script. Comments, names, high-level logic, macros, defines etc. will all be gone. They simply do not go into the insitaller but are a way to make scripting easier.