Regarding pinyin prompts:
I quite enjoy the fact that each syllable of the pinyin is being read to me as I type them, but that does not work after I have graded the word.
Now, when I make a mistake, I like to type it out again the correct way, to teach myself a lesson, so to speak. It would be nice if I could listen to the recordings as I do this.
I imagine this would only require copy-pasting a single line of code, but I don't know anything.

http://img849.imageshack.us/img849/6748/screenshot20121202at709.png

Good point. I've made an adjustment to this; try it out on beta and let me know if it's working as you desire. It wasn't a one-line change, but not too tricky, either.

It does. Except, only for compounds. Single character words only play the sound when I press enter.
That is to say, I no longer hear the words as I type it, initially.

Single characters never played the sound as you typed them, though. We did that because we knew we would be able to play the correct audio right after you typed it because you'd hit enter, and it's less useful in this context to play it as you go with the tradeoff of sometimes playing wrong sounds when you make a mistake.