BuddyPress.org

It worked just fine untill I installed BuddyPress.
First I tried to use buddypress approved themes (not BP themes) but they looked really bad. Pages would load normally but none of the BP functions would.
Then I switched to BP themes and after that nothing has loaded properly apart from the first page.

-deactivated BuddyPress plugin
-changed Permalinks to default
….and everything works beautifully, except for Buddy Press (which is no longer active).