BuddyPress.org

seems like BP 1.2.4 was tested with testbp.org only, which unfortunately is not running on WPMU anymore…..would be better to have a testbp.org with Single-WP and another test-website with a WPMU-install.

This would also help developers to compare their own WPMU-BP-website against a default WPMU-BP-install (like testbp.org but with WPMU).

https://buddypress.org/community/groups/how-to-and-troubleshooting/forum/topic/buddypress-1-2-3-to-1-2-4-ugrade-fail/