How can I get the AI to avoid each other (and the player)

Quite an old comment but in case anybody else comes across this. This is covered in the comments in CrowdManager.h. But to repeat them here:

/*
 *  Actors that should be avoided, but are not being simulated by crowd (like players)
 *  should implement CrowdAgentInterface AND register/unregister themselves with crowd manager:
 *  
 *   UCrowdManager* CrowdManager = UCrowdManager::GetCurrent(this);
 *   if (CrowdManager)
 *   {
 *      CrowdManager->RegisterAgent(this);
 *   }
*/