Hey guys,
I had replied to this again a couple hours ago, but unfortunately my reply doesn’t seem to have been registered.
Anyway, I solved it looking at the import dialog of my new project and comparing that to the old one.
The reason none of the scaling / rotating / repositioning changes were accepted by UE4 was that the box for “Transform Vertex to Absolute” was unchecked.
Checking it solved all of the issues…
In case anyone ever comes across this issue again: check your import dialog for boxes unchecked by accident!
Cheers and thanks again,
Til