Comment #10 on issue 842 by google....@ben.coman.com.au: ROTranslatingShape mouse hotspot mis-alignment http://code.google.com/p/moose-technology/issues/detail?id=842
btw, on review of above it looks like I didn't mention some of my musings about part of the problem being the use of extents throwing away information about negative position of shapes. I thought perhaps an offset stored per shapes, perhaps considered as a "negative extent", or shapes using bounds rather than extents might be required to make it work.
This consideration of "negative" translation of shapes may intertwined with "negative" translation of elements in http://code.google.com/p/moose-technology/issues/detail?id=831