I received a weird database error in the extension manager while trying to install eCart, Free Tools, and Data Bridge (Haven't tried Design Extender yet). I posted a similar message in the eCart forum, but again here is the database error I'm receiving in the extension manager during install. The funny thing is the extensions actually did install. Even though they all appear to be installed, they're not listed in the extension manager at all. Strange.
Design Extender installed fine
Mac OSX 10.8.4