Regards the “start section on” paging problem. Still investigating, but I was able to pin at least one problem with the inline page-break you can insert to your text. Probably should split text to different documents instead - however:
The inline page-brake -character position is incorrectly parsed. The page break happens from the begining of the wrapped row flow where the break is inserted. To overcome that bug, you should always have newline inserted before the break character. I was wondering why some of the text was lost and noticed it was transferred as “hidden white” text to the next page while it should have stayed at the previous page.
The the another bug (or feature?) regarding the “start section on” happens with the inline page-break. The section text after inline page-break is considered as “new section” and it forces it to start from the recto/verso even though it should probably still flow as current section.
I have to see if we had some page-break inserted or if it’s still some other flow bug.