Does changing coupling constraints on vehicles affect compatibility for savegames where the altered vehicles are in operation?
No - but if a combination that is in use becomes impermissible, if sent to a depot, it will not be able to leave the depot again without being re-arranged to become permissible by the new constraints.
Thanks. I just wanted to know if I could test rearrangements in my game since some EMUs in pak128.Britain-Ex seem to have their pantograph car either misplaced or drawn the wrong way round.
Ahh, splendid. Do let me know if you find any errors