The 32-Bit version of the Game is not compatible with the 64-Bit version of Windows, you should use the 64-bit installer instead.
Ok? I am now puzzled and really, really curious about that statement -> how did you managed to get a 32bit installer that ain't got captured by the WoW64 subsystem of the 64bit Windows OS? If it would include 16bit DLLs or some "I am to lazy to use API variables and rely on fixed system file path instead"-programming or whatsoever -> I could understand that, but that would mean syspecs below Win7, and that is the lowest version given in the specs... Under some *nix I wouldn't ask, but for Windows: How did you managed a (pure)32bit Installer/Game that couldn't be used under a 64Bit OS????
P.S.: I have tried the 64bit version on my main (desktop) system, but for my laptop i was thinking about trying both versions (32vs64bit) to see which one performs better... good to know now that I can't install the 32bit variant on it...
Honestly, I wouldn't know as it's not really my field but I also don't believe we'd be able to answer that question internally. We don't deploy the installer versions as those are handled entirely by the GOG team, if I had to guess I'd say that the 32-bit installer doesn't install the game on 64-bit systems and at least from my own test that appears to be the case.
With regards to 32-bit vs 64-bit, the game will always perform better in the latter and is designed as a 64-bit application above all else. Backwards compatibility is provided to 32-bit for Windows due to the still existant install base but generally, we recommend that users have a 64-bit OS where possible.