It's nice to be appreciated. =)
Too bad that we only got to basically nowhere. =P

There's already a big Thread at cdpred forums with users experiencing the same problem :
http://forums.cdprojektred.com/threads/56044-How-to-solve-script-compilation-issues-when-launching-the-game-with-mods/page13

But they don't say if its steam-specific, or a general problem. What's weird is, not all the users have it.

Do you have it on steam? If so maybe turning overlay off helps or not.. Just throwing things random at this point.

This is from Vinther of CD Projekt Red:

"If one's <gamedirectory>\mods folder contains script mods that modified scripts which were changed in 1.10 (and a lot of them were) script compilation errors will occur. I'm afraid those mods will have to be updated by modders to work. "

If you are still getting errors, the modders have not done their work properly. Contact the mod authors, since this is not a game problem.

Thank you, but that's not it. Any mod I'm trying to install have already been updated for 1.10. Not one of them works.

Okay, it seems i have found the problem. It's related to -- no love for the non-galaxy user. If you download the patch via anything other than galaxy, the files are corrupt.

You still should get help and direction from the mod authors. The game scripts have changed, and if it's not just you the authors will want to know. If it is just you, then you have an issue on your installation.