To spawn via script an object or terrain piece (tower, pillar, etc.) that blocks movement

I’m pretty much at the final problems of my tiny mod/tech experimentation. I’m trying to spawn blocking objects that… do what the title says. Problem is, my spawning of a pillar base in a custom game (while the game was running) did nothing, I could pass through it as if it wasn’t there.

Another thing is, I want the script to spawn them in locations, such as coordinates x-y-z. Is that possible?