When I try to download the Content Groove Agent 5 from my Absolute6 it keeps failing, what can I do?

I have just bought Absolute6 and most things have downloaded fine, a few failed but then did download on the seconded attempt. However, when I try to download the Content Groove Agent 5 from my Download Assistant it keeps failing after about 20 GB, what can I do? It has also done this for Tales and Backbone. Any suggestions? Many thanks in advance.