When I log in through the Open dialog to browse the battle.net map repositories, the cpu usage of the editor jumps to 100% on all cores and stays there indefinitely until I force end the process (I have tried waiting for over 10 minutes on one instance). I found that this happens even if I am already logged in (by using the options or other parts of the editor that require it) and regardless of whether I have a map open or what region is selected.
Specifically, the list populates itself up to a point (not sure if it reaches completion) and then the cpu usage problem occurs.
It can be avoided if the process is placed on a cpu affinity of one core. I have a dual core processor, so I'm assuming that reducing affinity so that at least 1 core is left free prevents locking up. I tried lowering the priority of the process but it has no effect. For those looking for a solution, you can change the affinity of the process through the windows task manager by right-clicking on the process name and selecting "Set Affinity...". Do this after starting the editor and before attempting to log in/browse maps.
After running it at single-core affinity, maps can be selected and downloaded normally, albeit slowly (while the interface is usable, it still feels sluggish).
I am running win-xp sp2 with a core2duo at 3ghz and 2gb of ram. The rest of my specs are adequate to run sc2 at about medium quality settings without lag (I usually run it windowed at low and get a steady 60 fps). I am running 2.0.9 patched yesterday and didn't use the editor prior to that (for a long time at least). As this seems to be a cpu/code issue, I won't include more information unless asked.
Thanks and please look into this as it might make the editor impossible to use for those who can't troubleshoot it on their own.
Edit: threads apparently pointing to the same issue:
Edit: added clarifications for those looking for a solution