InstallScript custom action not working.

[Manish Aggarwal]

Hi,
I added sample install script from ISWI help (see below) to my install. Then
created a custom action using the wizard (Type: 65536, Source: Test, Target:
<blank>, Comments: Test).
Then I added DoAction to the event control for the next button on the
InstallWelcome dialog. I built the project and ran it, I did not see the
message dialogs. The moment I click next it goes to finish and the setup
fails. I also tried to have the simplest install script code and it fails
too (just MessageBox function call). Am I doing something wrong here?
Thanks!
M

-----------------------Install script
code---------------------------------------------------
// Include Isrt.h for built-in InstallScript function prototypes.
#include "isrt.h"

// Include Iswi.h for Windows Installer API function prototypes and
constants.
#include "iswi.h"
#include "isMsiQuery.h"

export prototype Test(HWND);

function Test(hMSI)
STRING szKey, svValue, svPath;
NUMBER nvType, nvSize, nReturn;
begin
RegDBSetDefaultRoot (HKEY_LOCAL_MACHINE);

szKey = "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\App
Paths\\iside.exe";
nReturn = RegDBGetKeyValueEx (szKey, "Path", nvType, svValue, nvSize);

// The App Paths key contains the folder where InstallShield was
// installed, followed by a semicolon.
StrSub (svPath, svValue, 0, StrFind(svValue, ";"));

if nReturn = 0 then
MessageBox ("InstallShield is installed to " + svPath, INFORMATION);
return ERROR_SUCCESS;
else
MessageBox ("Cannot determine where InstallShield is installed.",
SEVERE);
return ERROR_INSTALL_FAILURE;
endif;
end;