im trying to import a collision object into unreal but its not registering that there is one but idk what im doing wrong … in maya i took my model and made a low res replica of it for the collision … i named that Level_11 and UCX_Level_11… exported them together with smoothing groups smooth mesh and triangulate all checked and referenced assests content unchecked … then in unreal i imported the fbx with auto generate collision turned on and one convex hull per ucx turned off … when it imports however nothing shows up for the collision , can anyone help me with this ? … ( for some reason could it be that u can not create a collision object using the main models geometry and have to create one from scratch from a primitive ?)
All collision geometry that comes from Maya needs to be a primitive type cube, must remain rectilinear- i.e you can move faces and verts, but they have to be planer and you cannot rotate the cube. You need to name it the same as the model.
UCX_myMayaModel_01_01
UCX_myMayaModel_01_02
Make sure you have no open faces on your UCX mesh. I’ve been doing modular meshes and I keep forgetting to close up the holes in the collision mesh, which results in it not importing. I hope this helps!
i seemed to do all of that but nothing shows up for the collision object … is there a poly count limit to how high the collision object mesh can be (maybe thats the reason?) ?
Turn off “auto generate collision”, after that it should work () 
When you still have the problem, post a pic of your mesh + collision boxes + information about your mesh (e.g tri count)