I'm having same problem. "running as administrator" does not help. I've tried 4 different versions of QTM. Ver 1.10 gives me the cookie error. Ver 1.9, 1.5 and 1.3 allow me to log in but don't give me options for category.
I downloaded Ver 1.10 again and the new download doesn't work either.
I don't see anything on my computer that might be blocking my cookies. I've checked my security settings in IE and they are set at the default.
Does anyone else have an idea what to try next?

@Uwe:

A known possible reason for that is using a proxy server like GT Guard or BT Guard. It will effect download, too, so the global effect on ratio is even.

I'm using BT Guard. Could that be why my ratio is so low even though I have a dedicated computer just for torrents with 50 Mbps down / 5 Mbps up connection running 24/7 uploading all the time and my ratio is still only 0.841? uTorrent shows lots of GBs uploaded and my ratio per torrent is always a minimum of 1.5 so it makes no sense that my ratio on this site is so low. I'm on two other torrent sites and my ratio on both of them is always over 2.0 . This site has always given me a low ratio. It drives me crazy that I'm uploading all the time and I still have such a low ratio.