Wow. Though I feel a bit dumb, it was good learning today. I better understand several things now. I attached a screen with a fairly large grille-model. Models like that need to be set to POLYGON, since I need to pass them. For all other things I use hulls, but let them calculate via c_updatehull. So, for dummies like me (I can't be the first to run into that wall):
action BBPolyPrecise () {
wait(1);
c_updatehull(my,1);
my.flags |=POLYGON;
set(my,POLYGON); //Both lines necessary?
}
action BBStandard () {
wait(1);
c_updatehull(my,1);
}
And thanks all.