Customisable Klein bottle (OpenSCAD)

I saw this (quite old) challenge online:
https://www.makerbot.com/media-center/2011/10/11/openscad-challenge-klein-bottle

I could not resist making my own! I'm perfectionist, I made it as perfect as I could.

I made it using bezier curves because that was a lot easier than trying to model the shape by removing "donnut" shapes around it (I could not see a neat solution to do this). Since there is no bezier functionality in OpenSCAD, I had to create my own, from an existing library found on thingiverse.

The bottle is easy to customise. I added 4 variables at the beginning of the files:
- wallThickness
- bottleHeight
- bottleDiameter
- tubeDiameter

The "precision" (number of polygons generated) is also configurable. I set it to 180 to generate the STL files. I might have exaggerated, the STL files are quite large!

I also uploaded a "cut" version to see inside the bottle. That one is for education purpose, and also to prove that I didn't "cheated".

Bezier library: htt