Hi:
I'm not clear on what you're trying to do. SAS OnDemand for Academics, if you are an individual user, just uses SAS Studio and there is not any download required.
If you are working with a professor, then you must be invited to an OnDemand class and there may or may not be a download depending on what your professor has set up on the OnDemand server.
If you are using SAS University Edition, in a Virtual Machine, then there are potentially 2 downloads -- 1) download and install of the Virtual Machine hosting software (VirtualBox or VMWare Player) and 2) download of the Virtual Machine with SAS inside.
Can you clarify what it is you are trying to do?
Cynthia