Sorry I've been absent for a while, I've been sorting out moving into uni and admittedly lost a bit of my motivation after the frustration that was the freezing for Atari 2600 games, for which I apologise. However, I'm back now, and Matthias has given me a helpful pointer as to where the problem might lie with the 2600. I'll hopefully get this support working properly again... perhaps a few more surprises too ;)