Cannot Install Themes

I already made a post about this about a week ago, but cannot for the life of me find it!
Anyway as hard as I try I cannot install themes:
I upload them, they become available in the selector, and select them, but it’s always stuck on that stupid ‘kubrick’ (which would be an awesome design if 100s of blogs didnt already use it)
Can anyone tell me what’s up? Am I doing something wrong?

My blog address is http://blog1.avxworkshop.com/
If you seriously think you can fix it, fell free to register and send me an e-mail at the below address, and i’l upgrade your account to administrator so you can fiddle with it.

ecable -at- avxworkshop -dot- com

Please help, Anybody!