I think there may be a couple of regressions that have crept into the last couple of builds that you might want to know about. If you take a look at http://www.yui-ext.com/deploy/ext-1....enu/menus.html with IE7, you'll see a gap has appeared in the buttons that are hovered/selected ("Toggle Me" button for example). Works fine in Firefox though.
I also no longer seem to be able to use either of the following doctypes in pages containing the toolbars in IE7. The rendering of the buttons seem a little strange when added. This worked fine for me in earlier builds, and still works fine in firefox.
Add either of the following to menus.html to demonstrate the issue:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
Keep up the good work - your efforts are most appreciated.