@sandykoufax, re:

> My wish for V4 is Diagnostic tool for joined surface to make solid.
> I'd like to make my model to solid, but sometimes it has result in joined surface.
> So I want to know which faces have problem.

For now the "Select naked edges" script can help with this, once you set it up you can then push the N key on the keyboard to make naked edges in the model get selected so you can see where the problem areas are at.

There's some info on how to set it up here:
http://moi3d.com/forum/index.php?webtag=MOI&msg=6051.2

- Michael