I'm having trouble getting the plugin to work correctly with a wordpress 3.0 install (still beta version for sure) but I wanted to post this and see about getting some direction. I'm using the network blogs on the 3.0 which is replacing WP MU as I'm sure you're aware of. I'm having all sorts of issues with plugins, but I'll just start with this one.
For one, it won't activate unless I comment out a few things. Here's the two main errors I'm seeing:
PHP Fatal error: Class 'BP_Group_Extension' not found in /var/www/vhosts/antiochnorman.org/httpdocs/wp-content/plugins/bp-group-calendar/bp-group-calendar.php on line 162
PHP Fatal error: Call to undefined function bp_register_group_extension() in /var/www/vhosts/antiochnorman.org/httpdocs/wp-content/plugins/bp-group-calendar/bp-group-calendar.php on line 264
any help would be great. Thanks!