Sheesh, that's VERY small images. Very hard for my old eyes to see any details.
Couldn't you have made them a tad bigger for the older folks? lol :)

This was fun last time, but since they are not from existing screen grabs... eek!
I recognise two at least, but the others? little chance :)

Guessed all except nr. 4. Perhaps little hint from gog staff :)? Guessing which game screen was taken from is not so bad. Worse if given title have few parts and you must guess which part is correct :-).

Do you both have MSN? I've added you all
Btw are they all from different games?

Do we need to guess the games of all of the five screens?
I think I have an answer just for the fifth, so far. Long way to go. :)

I do not have MSN, and I'm pretty sure they are from different games.

Can you get an MSN account? It'll be easier to discuss.

Can we get some hints now?
It doesn't look like anyone's gonna figure em out.

Hmmmmm, I think I've gotten all of them except for number 2.
I believe that Chemiefabrik means chemical factory though, if that helps at all.
Maybe two of them are from the same game.....

Perhaps, another clue might be that I think all games except number one are 3D ones and there is very fiev games that you can watch that kind of sign from so low above ground perspective. Cook said that all screens are randomly taken from playthrough...I'm thinking it's same game as number 3. Number 4 is what really puzzles me...

You are right, it's chemical plant
The next useful keyword might be Komplettlösung ;)

Thanks for the hint:)
Hooray I got one! I'm not completely dumb:)

Wow, thats hard. I only know number one (but not which game of the series) and maybe number five.^^

Lol I just got number 1 as well.
I played the game on a friend's pc years ago.
Don't recognize that screenshot from the game though.