Collectible Card Game Headquarters

When playtesting using "Computer - mad" I run often run into a problem where the AI will freeze at the card drawing step, crashing the program and requiring that I terminate it in task manager.. After it has done this once it will repeat the same trick every time I try to start again, even after closing the XMage server, client and launcher. Only after I restart my computer will I be able to play with the AI again, but then the problem will recur after no more than four or five games. Does anyone know why this is and how I can stop it from happening? Cheers.