@jschroni,

Sorry for the lag in getting to this. I'm just looking into these issues this afternoon, particularly trying to replicate the issue where the left-hand side of the quiz is blank.

Your account settings on this page...

http://popupchinese.com/account/review

... will control what sort of material appears in the popup reviews that show up on lesson pages. If this is set for lesson vocabulary instead of wordlist vocabulary, the system will draw content from any lessons we think you've studied rather than from your wordlist (if you access the review from your study center, it will always focus on wordlist vocabulary rather than lesson vocabulary).

Note: if you download everything from your RSS feed, that could trigger our system to think you've studied lessons that you haven't. If this is happening, just switch your account to wordlist mode.