Particles in container penetrating through wall

[JuhaHo]

One more thing, I don't understand. When creating tyCache, I get - of course the particles cached by frame tyCache_tyPart*.tyc- and then I get this gigantic tyCache_tyMesh.tyc -file. Is it really necessary? Can it be turned of or deleted? I think this is somehow included in backburner file, because the backburner files are getting really large, when tyCache is included. In fact they are getting too large for backburner to render.