Hi Pilou & Booleano - it isn't possible to apply a flat 2D plane onto a sphere without stretching or compression.

It's just a fundamental fact of geometry.

That's why Flow is not going to be the right tool for doing that.

Again, the technique that can be used for modeling a polyhedral shape is to draw polygons that have shared edges and then use Transform > Rotate > "Rotate axis" to pivot the polygons upward around the shared edge.

This is described and demonstrated in these previous posts:
http://moi3d.com/forum/index.php?webtag=MOI&msg=2140.46
http://moi3d.com/forum/index.php?webtag=MOI&msg=911.11

- Michael