Hmmm, what would cause this?...

 From:  Michael Gibson
671.5 In reply to 671.4 
Yeah, cracks between edges are the other part that is solved when you have a fully joined piece. MoI will do extra work along shared edges to ensure shared vertices between the meshing of each surface.

Since Modo is going to support vertex normals in the next version, I would assume that LW will do it pretty soon too... At least I hope so. That would make it easier for you to stick with LW.

- Michael