I’d be very careful about putting the mikrotik proxy in a production environment. It will work for some time 3days up to 1 month even.. but I haven’t had one sucessfully stay up yet.
Theres a thread detailing the problems this has caused for the hotspot system which currently relies on the proxy/web-server here: http://forum.mikrotik.com/t/hotspot-redirect-blocked-by-mt-proxy/19962/1