Problem installing Sins Beta

I have a problem installing Sins beta, cause when i have installed sdcentral and downloaded the software for the beta game its start installing the actual game, however it ends up in some kind of loop and start over after it tries to download activate.exe and comes out with odd values, like -52% or 112% and just installs the files again and again without actually installing them on my system...

I wonder if you could help me out...
im using vista.

Cheers,
Vul