Deflation problem using Kangaroo


I just started learning Kangaroo and I’m trying to recreate the vacuum effect of a meshbox around another object.
So far it works to let the meshbox “collide” with normal geometries f.e. spheres and boxes where the meshbox shrinks around. But I still have troubles when the object is a bit more complicated f.e. an extended rectabgle or even a 3D voronoi or the edges of a faceless cube (something with no clear inside and outside). Someone has some expierence with this?
Also the deflation of the meshbox isn’t working properly, when the pressure is to high (negative to deflate) the meshbox turns inside out, and will then inflate.
So far I can’t figure out what is wrong with the definition.

I’ve added the grasshopper definition.

Deflatable (90.4 KB)
Deflatable test.3dm (296.0 KB)

Thanks in advance.