=== Facing ===
It might be a bit confusing on the guard tower-main page so a info about facing here: looking to northwest if you want the door facing north( or 45 degrees to your right as mentioned) is correct, actually tried it out. Mentioned this just to make things sure, annoying when a tower is facing in unwanted directions.
=== Call rates ===
10 seconds delay between responses - tested a few times.