[vtrelut]

To me it sounds like a problem with a map mod. Could you try again by disabling your maps mods? In your MODS folder, locate all the "maps" folders you have, and put a "-" in front of them, so that they are renamed "-maps". If you have installed Kleini_293's map mod, disable that one first by renaming the "maps" folder contained in his mod to "-maps". Try again to launch the mission.

This kind of problem also happened to me, possibly because of some conflicts between maps mods.