I've written a VB program as a tool for VB SW Addin development. It cleans out all of the registry entries for the addin .dll, including SW addin keys and toolbar key entries. I find this to be handy when doing multiple compilings of a program.
If there is enough interest (1 person), I will post it.
Since registry editing is a sensitive topic, I will make the source code available and not just hide behind an .exe.