I have no idea how to build this concept. Help?

[mobius]

I have a concept of my own I could use some help with:



I'd like to design a device so pressing the red button releases the bugs 1 at a time, in random order (only once); in other words they exit the trap and come back and remain stuck again. I'd like each bug to be only released once per "cycle" or press of the button. Also I don't want to allow pressing the red button more than once while the bugs are being released (this part I sort of already have a solution for) I want the bugs to be released slowly enough so the player has plenty of time to view what is happening (so a second or more in between releases) thanks.

All the bugs should get released, just once. The top one must always be last. The order should be random and random each time the red button is pressed. The button can be pressed again once the cycle has stopped (the top one is released)