I have no idea if it will help or not, but if you can't get anything else to work, you might as well try. So if you are game, head on over to MoDaCo and follow the instructions in this link for "downgrading" your device:
The Ultimate Pulse Owners Guide - Android @ MoDaCo
Once you've done that, you might be able to install either an older 1.5 ROM or a new 2.1. There are a number of good "guides" for doing pretty much anything you might want to do in that thread.
Incidentally, the stock ROM's are really not as good as the modified ones, particularly, I like the FLB modified 2.1 ROM. YMMV