okay, this explaination might be too technical for some, but I still write it:
The whole scripts on the page are PHP, as you probably know. To stay logged in, the line "session_start();" has to stand on top of every page loaded in the browser. The index.htm on broodwarmaps.net does not have it, because of course it has to be php...
I will try to replace index.htm with index.php with the additional line, maybe it works...