John,
I has a similar problem with TS2010 a few months back. This was the response fron Auran that fixed it.
"Can you please run the 'network diagnostic' tool in Content Manager. This is done by opening Content Manager, then clicking on 'file', then on 'network diagnostics'. Once this has completed, please copy and paste the results into your reply to this ticket.
Could you also please try running an extended database repair in Content Manager.
To do this, first remove all items from the downloads queue, then go to 'file', and then click on 'extended database repair'. Once the repair has completed, please restart Content Manager, and then try downloading again."
Hopefully it will fix yours. A word of advice. Content manager is slow & un-reliable but conveinient. You may already know this, but for the benefit of others.
If you go to "Download Station" (click the "Download Station" button on blue bar at the top of page); search for the asset; click on "Download page";Select "Download (FTP); You'll find you can download 2 assets at a time & do it much quicker than via content manager. I'm not sure whether that is a daily limit for downloads, but if nothing else, it's quicker.
I hope that helps.
Rob