When I highlight a paragraph and set the font size, the previous paragraph (NOT highlighted) also changes. A 14 pt paragraph followed by a 36 pt paragraph became two 36 pt paragraphs.
ALSO (trying to debug the same problem), when I copied the document in Mac Scrivener 3 and pasted it into Windows RC5, font sizes switched. 14 pt followed by 36 pt became 36 pt followed by 14 pt.
(I pasted from macOS to Windows running under Parallels.)
ALSO, I cannot highlight a pilcrow with mouse alone. On the Mac, I can triple click on a pilcrow and select the full paragraph. On Windows, that doesn’t work. All I get is the text, not the pilcrow. (I think it matters, but I may be wrong.)