Among other things install a VSTO

Greetings,

I have the following question:
I'm building an installer which does several things:
- Install a java application
- setup some settings files.
- install a VSTO file that I built with Visual Studio. This is an AddIn for Outlook.

The trick is that the VSTO file is essentially an Executable on itself, presenting a dialog that then installs the AddIn.

I'm using the following code :

# Execute vsto file   

  ClearErrors

  nsExec::execToLog '"$INSTDIR\some_subdirectory\VSTOfile.vsto"'



  # debug location

  # Dumpstate::debug

  

  IfErrors 0 vstoOK

      MessageBox MB_OK "Installing the VSTO returned an error." 

      Quit        

     

  vstoOK:

  MessageBox MB_OK "Installing the VSTO has now not in fact returned an error."

The code runs, the details panel shows nothing but I do get the message box that no error was returned. No VSTO installation dialog shows either. I'm kind of new building installation scripts. Can anybody give me any pointers?

Thanks in advance.