Hello all,
What I did was not optimal by any means, but I tried it anyway and stumble over something strange.
See the GIF. I superimpose the viola cue on the cello, but when I delete it, the cello notes stay in transposed position even if the clef is no longer there. Nothing could fix this except going in to Page view and then back to Galley again.
If this already has been reported disregard this post.