percussion legend not visible in drum part

Now I have wasted over an hour to try to make the percussion legend visible in a drum part. I managed to get it in the full score but not in the drum part.
It works in other scores but not in this big one. Grrrrrr

I have even tried to delete all players except of the drum part. Then suddenly the legend appeared. But when I undo the deleting dorico crashed.
Problem remains. Very very frustrated. I can’t publish the file due to copyright reasons.

At the end I had the idea to create a new drum set and copy for the old to the new one. This solved the problem finally.

So this post is just to let everybody know that this can happen (hopefully not in the next updated anymore!) and what can be done against it.