That looks good Rick-
really like the handle for what I presume is the fine focus control-

A couple of things-

Regarding your light source-
I read somewhere (I think I linked to it) that the light source should be daylight, since that is the native color balance setting for a DSLR, and that would give maximum DR.
Since you're using a slide projector, you could easily mount up a full blue gel in a slide, and do a custom white balance-

The other point is regarding film flatness-
If I develop myself, I don't use clips, and the sheet is undistorted.

However, films that have been developed on hangers are often distorted- by the clips, and the heat of the process, for colour films.
I've been having trouble keeping those ones completely flat myself, within the tolerance of the depth of field, which, as you have said yourself, is minute-

Looks like a very nicely engineered setup-