The error you encoutendered where in the usergroups manager of the acp no ? If yes, this is due to my hack coz if you don't remove the xml files in the includes/xml folder, then when bitfields are rebuild the one for the chatbox are still present but the database fields aren't ! So this is absolutely normal.
The option to define the alt1, alt2 colors, humm maybe but as there are already many options, I don't know if I should. Anyway I'll think at it