I've updated the page so that it works properly in IE9, at least (all I had to do was add the <!doctype html> header at the beginning, and that seems to be good

I've updated the page so that it works properly in IE9, at least (all I had to do was add the <!doctype html> header at the beginning, and that seems to be good practice anyway, so I have no issue with it). I have no way to test IE7 or IE8 at this point, and I don't like the idea of adding code that I can't test. If someone wants to volunteer their time to help me test those browsers with excanvas, I'm willing to give it a shot.