Great post and I only see it now, damn...
I am impressed by the quality of your work, congratulations and keep it up!!
I'm in the process of finishing my own hollow fish too, and for the drawing part I used APS3000 for the design and Hollow Board Template Maker to generate the stringer and slices according to the shape of my board. Both can be downloaded for free here:
forum.shaperoom.net/viewtopic.php?t=3619, (website in french but softwares in english - don't know where else to get them)
and believe me Hollow Board TM would have made you save a lot of time (you get a PDF with the complete skeleton of your board in scale 1:1).
2 suggestions, you do what you want from them
- the holes in the slices are not just for gaining weight: hollow surfboards generally use a vent that you leave open when out of the water so pressure is the same inside and outside the board. In other words, leave your board in the car on a sunny day and your glueing junctions might pop out due to the pressure difference in and out. So make sure all the compartments between the slices communicate (if I were you I'd drill a few holes in the last slices before nose and tail)
- the same vent can be used to empty water in the event of a bad ding on the rocky swedish shore... it can be made out of a radiator vent or anything similar and is placed on the deck somewhere where it won't hurt your body and legs. You can see it on this picture of my board (it was before I started glueing the rails - compared to you i started by deck and hull, then rails - now in place but don't have any pics yet - in alternated layers of 5mm balsa and cork)
So best of luck for the following steps!!
Phil