It always appears to happen if I log out a char near the AH in Protectors Enclave. If it's near the shrine for example its fine, but if I move that char to AH and relog it won't work.
Try setting it to full screen rather than windowed maximized. That mainly resolved it for me although I do get it still on occasion (before it was every time though)
I don't know whether they are the same issue but every time I went to the power tab a lot of them where flickering and moving places. I changed the view mode from Windows Maximised to full screen and that resolved it but doesn't quite sound like the same issue but worth a go.
It's not about playing before the Americans it's more the fact that I would only be able to play a couple of hours on Saturday as it is starting at 5pm and being at work all day Monday rules that day out so effectively paying