Ok, I just tested on clean installs. Worked fine, except when I altered the config file and changed the default location of the wp-content directory. I will work on fixing that, along with the erroneous error that is getting generated *before* you try and log in (affecting versions 2.8+).
In the mean time, for those of you who it is not working for, are you using that particular customization on your installs? Ie., as describe here:
Thanks, and feel free to email me with any debug info you find, my email address is inside of the readme.txt.