Retropology mesh behind scult mesh ?

Hi there :)

How my god I like the tutorial but it's soo long :)  Anyway I'm learning a lot of stuff.

Some questions here :

* I guess that if i'm editing my retropology in local view (/) and that I don't see my sculpt mesh, points do not align on its surface ? EDIT - I checked and YES, which seems logical.

* While your retropology mesh seems to be ABOVE the sculpt mesh, mine seems to be BEHIND it.  Is it because of a lack of geometry ?  It's making things difficult to work on...

* ....Because then, I have to set up the viewport shading to "wireframe".  And I can't see which geometry belongs to my retropology or my scult.  
Which brings another question : why are the vertexes of your active mesh white ? Mine show up black...

Thanks a lot.

Thanks !