Detecting Presence of Another Group next to a Selected Point(s)

The thread is here if you are interested in following the development:

I strongly agree, the SketchUp environment is intuitive and cool but seriously lacking in a lot of ways for a professional designer. Plugins need to fill that gap. I am attempting to create a product in a few weeks that can rival the big hitters like Revit and Chief Architect, I know I probably won’t even come close but I’ll give it my best shot.