Is Adobe targeting older versions of the software with the new manager?
Some of my plug-ins only work in the older versions of the software and I use a triple boot system with separate drives for Windows XP, Vista and W8. They each have CS3, CS4 and CS6 (I missed out on W7 and CS5).
After I updated CS6 to the latest version of the download manager CS4 no longer runs. I discovered today that it will if I am online. I am running a legal copy of the CS4 Master collection and has been running with no problem for years. I have a back up of the drive and used it to replace the whole drive in case there was an error somewhere, something I have had to do every six moths or so. That did not solve the problem. The licence allowed two copies and I do have it on a second machine at home and that still works. That machine does not have the recent CS6 update yet.
The original licence agreement for CS4 didn't require you to be online. My broadband connection is intermittent because I live in a rather remote place. It has been down for a few days and I could not work even in CS4.