Today went much better than yesterday. I had 2 one-hour sessions this afternoon, during which I scanned the Chipmunk docs and jotted some notes:
The second session was interrupted when a (somewhat rude and arrogant) user entered the IRC channel, bemoaned that it was "disgusting" that no one understood how to use Rubygame, and then proceeded to complain about "it not working", which turned out to be mostly user error (of course, this was promptly denied by the apparently infallible user).
On the plus side, he did offer enough fodder for me to file a bug report about window icons not working right on Windows XP if they're set after the Screen is made (which is the only way Rubygame allows them to be set, currently). I might do something about that later, but it's low priority. (I could probably foist it on one of the assistant developers; it's mostly just a copy & paste job.)
Seriously reconsidering my decision to hang out in the IRC channel while working.
P.S. I also imported Chipmunk 4.0.2 into the rubygame trunk (trunk/ext/chipmunk). I resisted the temptation to touch the code, though.