First of all, thanks for your work on a really slick client :-)
Like the subject says, LiveLizard doesn't work with the latest Moz release (1.3). I have made sure that the POST URL was correct, and I have tested on Windows XP and 2000 (Linux box is down). The window opens, but nobody's home :-(
I have created bug 3454; the gory details (JavaScript console errors, etc.) are posted there.
Thanks again!