Are you using windows 7? I know with mine, it has some issues about which windows to bring to the forefront in AH.
For example, while using win7 64bit when entering an arena, the 'loading' bar that I was used to seeing in XP does not appear.. but rather the computer seems to lock up for a few seconds while everything loads, and then I'm in the hanger.
My assumption is that this 'loading bar' is still present, but appears behind the main window instead of in front of it. It's not a big deal and does not affect the game at all, but I can see how someone could confuse this with a hard lock.
Likewise, when I have to download... whether it be an update or a map, the computer seems to 'freeze up' after about 90-95% of the download being finished, but that's not really the case. It is in fact processing the download, but the window that shows all the 'stuff' happening isn't present (once again assuming it's hidden behind the main window) and simply waiting sometimes 10-20 seconds rectifies the problem.
