Gog's custormer's service informed me that the game is 32-bit only and cannot be played on a 64-bit operating system. So I can't play it, as bot my computers are in 64 bit. But I won't ask for a refund : I bought it very cheap on sale and hopefully that problem will be solved one day...
I really love the game, can't recommend it enough! Only little problem : The abilities that open new ways should have their own menu, or at least should be highlighted as it is a bit tedious to look for them in the list each time you need them. OK, there is the shortcut menu, but it needs to be updated everytime you change your main weapon. But this is a minor concern in the overall greatness of the game. Buy it, you won't regret it!
I have fond memories of that game, but this version runs way too fast on modern computers and as a result is totally unplayable. Also, I had to select "no sound card" and no sound at all before being able to launch the game, it would crash at launch otherwise. One of those two reasons alone would be enough for me to ask for a refund. 6 bucks for a game of 1995 is a bit much, but would be worth it if it worked properly. Which it doesn't. Fix it and I'll buy it again.