[MODO Indie] Is Show Geo Edges totally broken?

Beddall

Hey,
Anyone know if the 'Show Geometry Boundaries' in MODO Indie is broken? It just seems to join random vertices with highlighted edges... sometimes it will join ones that aren't even topologically joined.  It all seems a bit random and the highlighted edges on one mesh will change even though I am editing a different mesh. 
anyone have any idea what might be going on?.. and even better yet.. how to fix it?

There doesn't appear to be anything wrong with the meshes. I have welded all verts and run the mesh cleanup. Sometimes... cutting an element from one mesh and pasting it to another will get rid of the random display of edges... but only sometimes. 

cheers

Beddall

update: so, deleting the materials from the shader tree solves the issue... however hiding them did not. I actually have to delete the material group. So although I now seem to be able to fix the problem, I'm still no wiser as to what was causing it really. If anyone knows please feel free to let me know  cheers.