Thanks JScones. I had an attempt at getting the install path from the registry to work yesterday, and uploaded a test version to my FF page that used:
Code:
DefaultDirName={reg:HKLM\Software\Microsoft\Windows\CurrentVersion\Uninstall\SH3 Commander_is1,InstallLocation}
That works, but of course the code you've posted is more flexible as it includes the extra bit for defaulting to the install path as a fallback, so I'll make a new .exe using that code.
Good to learn about these things. May come in handy for future projects!