Yep, exactly the same symptoms here. I was running with Vista 32 on both boxes and everything ran like clockwork. I'm now running with Vista 64 on a brand new primary box and am having issues.
1) When EQ2 is running on the primary (windowed or maxed), I can no longer move the mouse pointer onto the secondary box.
2) When running in windowed mode, if I move the mouse pointer outside of EQ2 and onto my primary machine's desktop, the mouse pointer 'disappears'. If I click somewhere, it will reappear, and then I am able to move onto the secondary machine.
3) The secondary machine is obviously running the same, up to date, version of EQ2 and continues to funtion without any issues. So It doesn't appear to be an issue within EQ2.
So I'm wondering what it is that is suddenly causing this. Is it simply the fact that Multiplicity isn't happy with Vista 64 on the primary box? Or is it that Vista 64 treats the mouse pointer differently to Vista 32?
Given the fact that the mouse pointer behaves oddly in moving out of EQ2 even before I attempt to switch to the secondary box, I'm assuming it's this second guess. Either way, it unfortunately makes two boxing impossible and makes Multiplicity redundant

I'm reluctant to rebuild the box with Vista 32 as it's taken 2 days to build already.
Interested in any views on this.....
Pete