Why can´t I find any changelog for a patch?

I know GOGs version is still 1.0, but what do we miss without the updates which steam users got? What bugs have been patched?

At some points in the game, there are multiple ways to proceed. Do they all work in the GOG-version or are some of them bugged?

After some (excessive) research:

There are 2 achievements bugged.

1. is an achievement which you get for unlocking all of the achievements.

2. The penny pincher achievement doesn´t work but the action in game you have to do in order to get it works.

Conclusion: The multiple ways to solve a puzzle reward you with specific achievements. Those achievements work, so all of the solutions should work too. The penny pincher achievement doesn´t work but you can still do the action in game which is required to get it. The achievemet just doesn´t register.

There is also an easteregg which was patched out in some of the releases. From what i´ve read, the GOG-version
still has it. So maybe the non-updated version isn´t that bad after all.