When you add a physics rigidBody type Box, it is not calculated at it should be, there is some dimension bug.
(Like most 3D engines , we expect some correct dimensions to be generated, i think this will annoy users to have to manually tweak something that should be right)
While convex works very well
It looks like "convex" is the only way to get correct dimensions and works for cubes and cylinders perfectly also.
I have some questions :
1 ) Perhaps removing box from the Physics menu ?
2) Bring new cylinder type with parameter for number of faces we want tyo optimize physics ?
3) Allow users to choose their own collision mesh ? Or use collision mesh included in the model FBX file ?