The original version has a check point saving system. Later on a normal saving routine was added to the game.
What system does GOG's version use?

Well GOG is always the latest patched version of the games they carry right? I would assume the later system then. I wanna buy this but I have the disc version so I can't go GOG happy again.

I make the same assumption as you my friend.
I'd like to buy this game, because my disk version doesn't work any more.
May anyone confirm the saving system in use?

I haven't played this game before but,
After Christoph gets out of bed, i was able to press 'ESC' and save the game in one slot, so i'm assuming it's possible to save at any time, right ?
EDIT : Just found a readme in the game folder regarding the patch.
"+ Save Anywhere (Escape menu option) (NOTE: Certain Disciplines may not work properly for a short time after reloading a save game. As such, we recommend saving your game in areas where you don't anticipate needing your Disciplines immediately after reloading)."
This is one of the features mentioned in the patch readme.

No problem. Have fun ;)

@Namur, I rated your post positively for the same reason! very useful info! :)

That's good to know. Thanks for the positive feedback.

check point saving got replaced by a Free save system with Patch 1.1. Dunno if it still autosaves while changing sector

Yep, it does.