I had a very similar problem and all resolved questions from the developers seem to say its a problem with the Jquery from other plugins. This didn’t make too much sense to me as the display was the issue, but even after uninstalling all plugins and trying various themes, I eventually had to go into the code and play around to fix the problem.
Solution:
My display problem was the comment input box had some weird jag below it almost like a half a input box (note: this was for the fly in version even though it happened on both types). Turns out the background image used had part of an input box drawn on it to make the inputs seem rounded. I removed the line that used that background image and it looks fine now.
Basically use firebug to find the elements you need to work with and play around with the code until its fixed, but make sure to have a back up before hand.
Its really weird because the plugin works on their site, but I have no idea why not so many WordPress installations. Oh well hope this helps you guys.
– MrJman
