coupled edge synchronisation on cyclic baffles
Coupled edge handling was not correct for cyclic baffles. This gives some obscure error message about not being able to find transform.
This is solved in Foundation dev 001e172fed1d4ef231fce4f6f94439df86bb0fcf. If it doesn't give any problems we might want to merge this in early (i.e. before the next big re-sync)