Dan,
Thanks for the effort, I'll give it a go and report back. 
Regarding fret slots, what cutter are you using ?
Also are you considering string numbers ranging 4 to 8 , compound radius, and fan fret instruments ?
Hmm... "whoa!! baby steps!"

At the moment I'm using a very narrow (20 degree) V cutter/ PCB engraving bit I picked up on eBay, really just to mark the fret slots so I can take my (manual) fret saw to them. I have to say I'm only looking for this script to produce something I can take and hand-sand to final shape since so much of neck work relies on having the instrument fully assembled and under string tension.
I do have a PreciseBits fret cutting bit in mind (item #MM3I8-0230-009FC) for the eventual cutting and I think StewMac also sells one. They're a bit pricey and at this prototyping stage I'm trying to avoid the waste of time and money on broken bits. I've put the PreciseBits cutter on my Christmas wish list.
This script is tested to 5 strings on a 35 inch scale length. I'm focusing primarily on bass layout for now but the concept should carry over to guitar with little to no modification. The attached picture shows the result of a 22.5 inch scale length 4 string "micro-bass" (similar to Liuteria 3G).
I will eventually get to compound radius but for now this only handles fixed radius. Fanned fret is also a future improvement but my son, the bass player I'm doing all this for, doesn't really like fanned fret basses so it's pretty low on my priority list.
I failed to mention, the radius cutting is based on 10bulls' sloped surface and should be cut as an engraving operation in a similar way (0 depth, no optimization). The fret slots should be engraved as well but depending on the cutter I imagine using multiple passes and appropriate feeds and speeds). Everything else is your usual pocket or profile as you'd expect.
Also, I sort of shamelessly lifted the MakeNewLayer function from one of your own scripts. Thanks for that! If I recall, I also borrowed some concepts from scripts submitted by lloydsp and dh42 besides the aforementioned 10bulls so all credit where credit is due. I felt like I was borrowing so much that I should give something back. I do have a "Sloped Surface Following A Polyline" script I've been working on (also based on 10bulls' and others' concepts) for defining the belly cut contour on the back of a bass body. I will share that after I run another test or two.
As mentioned, there's plenty of room for improvement in this script. Like, I realize if I connect the arcs that define the fretboard radius then the machine won't get such a workout in the z-axis and I also realize the radius is only approximate since I and using an end mill and I'm not properly compensating for the bit diameter. Any software is a work in progress until it's no longer used. Your feedback is appreciated.

D