USB Devices fail to work since 30 December 2008

Here's the situation: I have two USB devices that have refused to work ever since the update released the end of December 2008. They are the following: PICKit 2 (for programming PIC units), and a simple USB to Serial adaptor.

I have repeatedly re-loaded "Tools", have re-installed every conceivable version of Parallels, and the only way I can make my devices function is to put my old Version 3, Build 4128 back on the machine. At this point, I am now out close to $1,000 in billable time, and the folks at "Technical Support" don't seem to have a clue, except to keep telling me that I need to load the version(s) that don't work!. I have also offered to provide them with a duplicate device so that they can figure out what to do. My latest response from Tech Support was "you have old version - you need to load new version for things to work"...

So, do I just write of Parallels and go purchase a Windoze machine again, or what? I can't keep stalling my clients.