My solution is to simply run pfSense in a virtualbox under a minimal linux host (I installed ubuntu from the minimal.iso and selected minimal mate desktop). I configured wpa_supplicant on the linux host to associate the wireless adapter to the AP, and then bridged it to pfSense as a WAN gateway. I have a triple-WAN setup with failover (not load balancing) with FiOS, xfinity and cellular broadband as the WAN gateways. All good, it works great.