Update:
I really don't know why and how... but Fallout 3 runs now flawlessly (so far) !
I installed various mods (Command Extender, Updated Unofficial Fallout 3 Patch, FOSE, Enhanced Blood-Textures, Fellout) still didn't work.
Then I ran without mods again. No change. Still crashing after the first slide (well at least its STARTING!)
At some point, I was just scrolling through the mods on Nexus... and installed the "better High Detail Map and Icons".
Now I got a message instead of just closing! "program stopped working".
And guess what: after I uninstalled the "Better High Detail Map and Icons - mod"
the game launches and I can play!!! FINALLY!!
I tried getting the "Better High Detail Map and Icons - mod" again, but this time I didn't change anything in the configuration-screen.
Now the game works just fine!!
It doesn't make the slightest sense to me, why installing and deinstalling the mod makes my game finally run properly, all of the sudden.
But I'm happy it runs at least and hope someone can use this!
(Still in the "growing-up section" ingame. I will report back after I leave the Vault! Wish me luck!)
