HTWingNut: Thanks for trying to help. I did edit ini files, setting different resolutions and setting window mode on or off (assuming "StartupFullscreen" is the value to set to false?)
Edit: I tried on my laptop with i7-5500U, GT 940m, and Intel integrated GPU, with Windows 8.1 and still same issue.
floccipocci: Did you try installing using the installer downloaded from GOG website? Instead of using Galaxy.
This may sound far fetched but I found that there are errors in the game which is installed from Galaxy. I had to use the downloaded EXE installer and then the game works.
Might be something wrong with the install settings or registry or game path when using Galaxy to install. Theres another thread where we had a problem where the sounds are missing and a critical game function not working. Like the game is using the wrong engine or files.
Yes I discovered the missing sounds with the Galaxy version as well. I uninstalled the Galaxy version and reinstalled with the manual launcher from GOG.com. So far the sound is now working correctly.