Sewing the mesh sides to the canopy looked to me to be the most difficult part of the Bilgy tent. SO I was happy to see this
http://www.rayjardine.com/ray-way/Tarp-Kit/Net-Tent/index.htm
Which looked to be much easier to make, and also to "design" by modelling (prototyping) in , say, tulle plus blue tarp material for the bathtub floor. Get this to a comfortable size for the three of you, then source a tarp to cover. I'm sure this inner/outer concept would be much easier to make (no triple seams on a taper for example as in Bilgy)