What do you mean?
I created them as 32x32 defs then I place them on rock (black) 10x10 terrain and I open a small 7x7 area view when have to select, so the player see ONLY the symbols and can click on them. After he do the code, the symbols are covered again with fog of war.
There are two gates, one desactivated and one activated. Both defs replaced monolith exit/entrance to be able to place them with UN:I.
When player did the right code, the inactive gate is replaced with the active one (refresh screen), and the player can pass through. After that, the gate is again replaced with the inactive one.
One thing more
My "flying boat" (thanks to illusion created by shadows)
I created also a special "water" terrain, so no more beach on swamp/sand, it is passable and anything can be placed under it and accessible by heros.
I need it to place Atlantis city on water, but being accessible by walking in.
For now only 192x128 available because I only need that one.