Mark,
I was playing around with your site, mind if I ask a favour? You've got the link to my site set to
http://www.roadtogrammar.com/index.swf , which goes to the old version, the latest version is
www.roadtogrammar.com (splash intro) or
www.roadtogrammar.com/welcome
Incidentally, I'm working on developing learning games for my 'real job', hopefully we can share some knowledge there.