Is it not possible to include the first bar in second endings in a multimeasure rest?
I think you’ll find that if you set the second ending to use the “Open, short” appearance via Properties it will allow a multi-bar rest to appear, but really it should allow it even if it’s set to the full open appearance: I’ll make a note of this and we’ll improve it in future.
It didn’t make any difference, I’m afraid. But thank you for your answer. For now, I can include more bars in first ending to solve the problem.