I've noticed this seems to be an annoying bug with CMP in 2010 - especially if you have a large amount of completed downloads in the list, one particular item will seem to hang at 99% complete for no reason, with the connection speed gradually dropping to zero. The trouble is, this bug tends to also mean that no matter how many times you cancel it and restart it, it basically keeps it stuck at 99%.
The only way I've often been able to download content mucked up by CMP in this way is how I presume Jaymom really means - the so-called 'Black Pages' accessed at the 'Download Station' link at the top of this page. Then instead of downloading an item using CMP through the 'Download' link, try downloading it via FTP, and then install it manually in CMP. It should work then - in fact, I've had only one or two items that even refused to download through FTP (and that was because the actually item wasn't uploaded properly).
Of course the problem with FTP is you then have to do a bit of a search for any dependencies that content might have, but at least this is an alternative.
