Project with multiple animated compilation suddenly messed up

I've worked for hours on a project with multiple animated compilations. Suddenly the whole animation (all compilations are completely messed up). Some elements arent visible (only boundry boxes of the elements so you can move them but they're not visible). Some animated elements have a completely messed up effect. Some illustrator layers suddenly appear as rectangle (where in reality they have a dynamic shape with animation. In a previous auto-save it's still working properly.  If i go back to the last autosave, I've lost a lot of keyframe animations. Does anybody recognize this problem?