This may be something you are already aware of, but VS2005 uses the extension .vpp to store and retrieve system diagram files. I discovered this by chance, when trying to locate sample files from the trial download for BP-VA 1.1. Any comments?
I found out that, given the timestamp, extension vpp must have been something Visual Paradigm assigned when trying version 2.2 of the suite time ago on top of an early build of ours that I used in order to try out the suite. The files had not been removed, so they were naturally found by BP-VA when looking for projects to open. My appologies.
Sorry for my late response. It looks like your problem was solved. Am I correct? Please feel free to let me know if there are any unsolved issues.