Only CAPsMAN needs a manual trick to make it work. Not sure if you are using that, or if it is just a single hAP ac with VLAN? In case of the latter, just do VLAN filtering on the bridge (which is very well supported with the new driver).
VLAN filtering:
http://forum.mikrotik.com/t/using-routeros-to-vlan-your-network/126489/1
CAPsMAN with VLAN:
https://help.mikrotik.com/docs/display/ROS/WiFi#WiFi-CAPsMAN-CAPVLANconfigurationexample: