Those onehundredboardz look amazing. I'd be interested in doing a replica build of other DivII design e.g. Davidson, Tornado, M1 etc. So if you or anyone else has access to the design lines that would be great. I'm currently working on my 2nd Lechner build, experimenting with slightly different build techniques.
The link you shared should be
www.seabreeze.com.au/forums/Windsurfing/General/Building-a-hollow-Division-2-sailboard and I've updated my documentation to a new website
buildwind.surf/