I made a new release of Hanzi Quiz today.
I also modified the code so it remembers the answers to recently-asked questions and doesn't present them as choices in subsequent questions. Besides having more quiz data (which I hope someone else will do), this is the only request I've received.
I have to keep calling friends of mine with Macs -- "can you check it?" -- what a pain. There's still a problem rendering one of the pinyin accent marks in Mac IE, and those characters just show up as boxes. I assumed there must be a font install to fix this and rolled on with the release.
A friend of mine checked it in Safari and the question and all of the choices are blank. The (empty) choice buttons are rendered fine and work, though -- you just don't know what you're choosing. Sounds like another browser adventure I'll save for another day. If I'm lucky, they'll fix their code before I get around to trying to "fix" mine for their browser.