I had a brilliant idea for my last exam - each question would have an identifier that included the chapter.section number, plus any other tags. For that exam, I only used the section number. Everything went well, until I had the marks computed. most of the marks would not show up when I click "look at marks" or when I created the spreadsheet. (those two tasks may possibly be doing the same thing). This of course, was a huge problem. Note that the annotated versions of exams were annotated correctly, including the score.
It was only after this that I read in the manual that you shouldn't include decimals in the name. I thought this exam was totally and completely screwed up. However, I read in the manual that you can change the scoring in the latex file after the fact to test different scoring scenarios (without having to recompile). Could this possibly work with the question identifiers? It did! When I removed the . in the identifiers (replaced them with -) everything worked fine!
I don't know if Alexis coded the system this way, or if it was someone else, but I wanted to thank you for planning for - and preventing - the consequences from my own stupidity. (and apologies to the rest of you for telling you something you probably already know.)