I kinda sorted out the crash problem, if I attach the UCX to the mesh itself, or have them outside the group, it doesn’t crash.
However now the collision is not working when importing into Unreal, when opening the model in the editor, it shows “Num Collision Primitives: 0”.
If I reimport it, the collision appears, however it’s position is at 0,0, instead of being in the middle of the mesh… The pivots are the same place for all the elements, group, mesh, lod, collision, so it shouldn’t be offset like that. This is getting really annoying.