Am I missing something here because I don't understand what the issue is here. Please provide a little more detail.

Are you referring to the need to have each installed UD client customized with your existing name/password to the grid site? If so, there's no way to fix this. It's the way UD works, just like BOINC.

If not, the simple way to handle any software package that needs to be deployed to multiple machines is to download it once, and put the installer EXE on a network drive, burn it on a CD, put it on a USB key, put it in the deploying software image, etc. You should never need to download it more than once.

Then the only thing you need to do is customize the install (i.e. check "Existing User" and supply your login credentials). A small wrinkle in an otherwise simple install.