Sorry uploading avatars is disabled. I honestly don't remember why.. so I'll just pretend like it was for a good reason.
In part it is because the HTS forums are integrated into the site(which in reality means its a bunch of hacks stacked on top of each other.)
Version 3.1 of phpbb would make this easier and means we don't have to patch things ourselves any more every time someone finds something wrong with phpbb. But who knows when that'll be.. maybe there will be a new version of HTS itself by then that chooses to go with a totally different forum.
I apologise for the inconvenience.