The INVISIBLE flag for WMB entities makes them invisible, they are not rendered. Otherwise check your script, you set a wrong flag.
set(my,INVISIBLE);
No, sorry. I did not set the FLAG wrong. The same action attached to a model makes the model invisible, as I stated earlier.
Ok, so here is what I found, just incase someone else runs into this in the future. The invisible flag will not turn .wmb entities invisible. To explain further: I find, that if I make a simple block, assign the default texture, and build it, then load that .wmb into another level I have created, then set the invisible flag to on, either by action or in WED, the block is still visible after I build and run.
If I assign the NONE flag to the faces of the block before I build it into a .wmb, then load it into a new level, the block will not be visible in the level but will still be detected for collision detection, at least for c_move anyways (thanks bart_the_13th). No need for any flag to be set.
This is exactly what I wanted because I was using a terrain for the ground and a .wmb entity for a collision hull so the player would not get stuck in complicated models or be able to climb places they shouldn’t. It worked perfectly.