I suffer from crashes myself that I can reproduce.

Attached is a screenshot of the error message I get.

Googling around (the error message and 'fallout') shows me, that I could not be the only one.

It seems that my savefile is corrupted now. I am currently in the wasteland because of a random encounter. The Radscorpions are dead and I can walk around and everything. When I go to the world map I am able to scroll around, but when I CLICK somewhere on the world map, the game instantly crashes.

Does someone else has this specific problems with the FIXT mod?

I'd say yes, the savegame is corrupted and no, it's unlikely this can be fixed. All similar problems I've seen so far, including my own, ended up in digging up an older save. Savegame corruption is one of the BIG downsides in both Fallout and Fallout2. Make sure you've got plenty of them. Sorry for the bad news.