I can confirm that it's only a couple of IE workarounds that cause the validator to complain, due to usage of <nobr> tags.
As for >>1, changing the HTML template might be something you want to do (or might not, depending - the current one is designed to degrade fairly gracefully, and forcing it to look the same in major browsers might break the minor ones more instead). But I don't see what's wrong with the script itself - believe me, if there was a way to do things more efficiently, I would have done it already. You're going to have to point out some actual inefficiencies before you can do anything about them.