Editing Mesh Colliders? Creating a usable pot/cup

and make sure that the objects falling into the cup are using primitive colliders rather than mesh colliders

Well, mesh colliders for the objects would work as long as they are convex. However primitive colliders are generally preferred where possible because of speed.

The objects falling in all use box colliders.

Removing the convex mesh worked, but now because its not convex it's falling through the scenery which is also a mesh collider. I can't make the scenery a mesh collider either, it makes the hit box work badly. I might be able to fix it by replacing the scenerys mesh collider with a compound collider if I can figure that out.

@Alienjesus: Does this pencil pot have to move? If not, remove the rigidbody. If so, make the collider out of a collection of primitive colliders, such as a ring of boxes.

I ended up modifying the scenery to use a compound box collider (it was a desk/bookshelf anyway, it's very square), and left the pencil pot (which does have to be moved) as a non convex mesh collider. I also changed my drinking glass object into a mesh collider instead of a box, but for some reason it falls through the desk now. :S