Thanks for the link.
Unfortunately upgrading to the beta didn't do anything to resolve the problem.
However, I did a little more poking around in the ATI software, since thats the only thing thats really changed on this system since it was working normally. I found a toggle in the "Hydravision" software that appears to have resolved my problem.
In the Hydravision properties in the Desktop Management tab, the second section down from the top is "General" The first toggle on the left hand side is "Application position memory". Well, apparently this is either bugged, or named incredibly poorly because if there IS a check in this box, FlashFXP always opens in that tiny tiny tiny mode. If I deselect it, I can resize the window, close FlashFXP and when I re-open it, its still the same size it was when I used it last.
phew...
Thank goodness. It's amazing how annoying little things like that can become.
Thanks for your help. Its much appreciated, and I deffinitely love your software.