I think this is the same as the steam release, which is an emulated ps1 version.

I don't know about the Steam release, but this is definitely an emulated Playstation version.

Also by default, the emulator seems to have mixed up binding of square and triangle buttons.
Thankfully you can hit escape to go to a rather bare-bones emulator menu, but it does allow you to rebind keys or controller inputs.

Honestly the best thing to do is after installing it is to swap out the pre-packaged emulator with your desired one. Saving via the normal save function doesn't work on their emulator and the settings aren't optimized to make it run and look as good as it possibly can on modern hardware with proper emulator tweaks.

I agree that you'd be better off using your own preferred emulator. But I did find the pre-packaged emulator fine. Didn't have any trouble with saving though. Might be down to the fact that I don't install Gog games to Program files, but instead to a separate folder on a separate drive, so the admin requirements to save are thankfully less of an issue :-)

Stupid question, but where IS the ISO? I'm looking in the game installation folder and can't find any bin/cues, chds, or large files that would suggest it being the iso.

EDIT: I think I've found it. It's in the Res folder, as "game.bin" and "game.cue"