Reproduction steps:
1. Open attached project (ReproProject.zip)
2. Open and play the "test" scene
3. Notice that the red plank doesn't touch the ground
4. In the hierarchy click on the "ObjPlank" under level 16 -> Button(Plank) -> ObjectAffector -> ObjPlank
5. Notice that the collider is misplaced (check error.jpg)

Actual result: Collider is misplaced.

Expected result: Collider borders should be the same as the MeshRenderer borders.

Note: When the plank falls on a flat surface the collider isn't misplaced.

By Design: The basePlank object has unsupported skew transform on it, so physics and graphics won't be in sync. As a matter of fact, it's only the physics collider that is placed correctly. The graphics plank overlaps the pillars since it takes skew into account.

Reproduced on: 5.1.4p1, 5.2.4p1, 5.3.1f1, 5.3.1p4, 5.4.0b3