MJC, what do you mean, it flashes three times? Do you mean it flashes like it's being minimized and restored, or like it's going from fullscreen to windowed and back? If that's the case, then I've had your problem before. And the solution is deceptively simple...
My good sir, you must click. Click like a mad man, like a spastic telegraph operator. You must be John Henry in the race against the steam powered clicking machine. You must click as if your very life, and lo, the very fate of the universe depended on it! For God's sake man, for all that is well and good in this world, YOU MUST CLICK!!
Well, dramatics aside, if you are indeed suffering from the same problem as me, rapid clicking ought to solve the process whenever this sort of thing occurs. You see, I'm not a coding genius or anything, but I have a theory. My theory is that ZC has a disagreement with Windows XP about resolutions, and I'm not talking about their respective goals for 2005. ZC runs at a very low resolution in full screen, something like 320x400 or something low like that. I think. And Windows does not like this. No, not at all! So being the bigger program that it is, it simply gives ZC a big old slap upside the head in the form of an access violation. ZC tries in vain on it's own, struggling to convice XP to let it run in a low res full screen, but alas, it has no luck.
But the clicking solution does work, for as the movie TRON taught us, Users have 1337 powers. If you click fast enough, you're liable to get a click onto ZC itself, and NOT the desktop. This is important, because for whatever reason, if you do it right, ZC wins the screen resizing battle and opens. I've had this issue with other programs, and not just ZC, so I don't think it's an issue exclusive to ZC. It's just a resolution thing.
Hopefully this will help. Good luck!