Well If you assign a surface that is passable to be a switch then it is only activated if you walk through it. If you edit a cog such as 00_elevswitch so that the activation switch is a thing and not a surface then you might be able to activate it by walking through the object. It might be diffeerent with 3do's but you could try it.
Also you can walk through _powerup parented templates when there's no cog tied to it so linking a cog to it would get it to send a message. The _powerup template spins though so in your master template file copy the line for _powerup and remove the angvec values from the line. Remember to rename the copied template to something new.