I've used bug #638 as the occasion to tweak the Clonk movement code. That's always an opportunity for hilarious Clonk behavior, but I think I've removed most of the regressions I introduced now, and would like to solicit some testing. There are engines on the autobuild page, I wish an Objects.ocd would fit in the attachment size limits (there are some incompatible engine changes), and the source code is in the movement branch in the repository.