I've had some performance problems with BA in general, but I assumed it's my laptop, I'm using a 2-year old fairly basic laptop and my hardware may not be fully up the job... BA keeps freezing up on me... the entire desk-top keeps slowing down a crawl, and the only way to fix the problem is to reset - obviously a major headache for me. (I'm using Windows Visa, so if my problem is the same as yours, its not in Windows 7). Like I said, it may be time for me to buy a new computer, BA seems to hog a lot of system resources.
You can imagine the problem. You put in one side of a trade, suddenly the whole computer freezes up, desperate you reset and log back on... only to find the other side of the trade was not made, the original bet stood in play and you lost the lot
Thats another issue I have with trading, one computer problem, hardware failure, API problem at Betfair, software problem, internet connection problem, a non-runner (rule 4) cancelling the lay side...you can't gaurantee that you will close the trade. You can lose the lot.