Hi Vincent,
there's no more info in the registry. At this point we have the assembly name and we know that it is not in GAC, so either it is in current directory or it's absent.
That being said, I think this is the wrong place for this change. Method get_file_from_strongname [1] is better suited for that purpose IMO.
Also MSDN states that assembly name is not equivalent to file name. I suppose that code to resolve assembly name into file name exists somewhere in fusion.dll, but I have never seen it. Hans may know more.