sounds like some good advice. I don't think i have damaged the heads as i caught the overheat early and toped it up almost straight away. it then did 50 miles home easily so im not too worried about that. As for the porting - i think thats either been done or the heads/cam are not standard as the timing was still out when i set it to standard. It's a real bitch to start it but once going - goes like a train, wheel spinning through the first 3 gears if i let it! (manual is so much fun!) there is bags of torque but i havn't done a rolling road to guess the bhp yet.
i recon your cam upgrade is a good idea - i'm happy with the crane profile description too (don't know a whole lot about profleing. I recon this company who quoted £50 for the diagnostics is a good place to start, plus they are local.