Algodoo

I've been trying to learn thyme, and it's been going pretty well, except for one thing. I can't seem to get if.scene.my.blank to work. Right now I'm trying to make a vortex like portal that can be turned on and off. Right now i have an on and off button (the green and red buttons), but i want just one switch. I tried making one switch using the grey button to the left, but i can't figure out how to make it switch from on to off. Some help would be great