[Closed] Port forwarding with a BT Hub router

I'm installing a wifi thermostat with web access. I've got it running easily using a linksys router, but I'm trying to install one using a BT Home Hub router and failing miserably.
Basically I need to open up port 80 to a fixed IP address on the network. The settings on the Hub for this are pretty tortuous and I can't get the bloody thing to work.

So,
1) It's asking for a trigger port. I've set this at 0, but are there other options I should try; and
2) Is it possible that the Home Hub just cripples any chances of getting port forwarding working - I'm sorely tempted to replace it with a linksys or similar.

Any other words of wisdom or caution gratefully received.