The fix Geoff refers is about anonymous user who couldn’t add an organizer or a venue, yours is even more specific 🙂 I installed both plugins to fix those issues.
I had the same issue with version 4.0 (events calendar pro + community events + filter bar) and resolved with the fix that Nico gave us : http://m.tri.be/fix41497
@ Nico Santos: Could you let the devs know about this issue in 4.0 so they can fix it in the next release of version 4 ?