You need two control sectors, and the door and button sectors, and give the button sector property 975 (Linedef Executor: Touch Sector Floor)
You use one control sector for the door, and the other for the button as follows: Give each control sector a linedef type 97 (Linedef Executor: Trigger Each Time) and a linedef type 106 (Linedef Executor: Move Sector Floor.)
Tag both of one control sector's linedefs to your button sector and set the floor of the control sector to be zero, with will cause your button to depress into the ground to the height you set, which is zero.
The door is a little bit different. You have to tag the linedef type 97 linedef to your button sector (not your control sector) and you tag the 106 linedef to the door sector on your map, setting the floor height of your door control sector to zero.
This should cause both your button and door to depress into the floor whenever a player steps on a button.
If this doesn't work, let me know, I may have made a mistake in the instructions.