I needed a replacement gear for my son's Powerwheel ride on toy. I couldn't find a good customizable gear having the two rows of teeth. So I took the code from the Customizable Involute Spur Gear by atartanian and basically copied it twice. I translated the top gear to go up the height of the bottom gear to combined them together. As my son would say, I'm a "noob" at OpenSCAD, but this gear seems to be working well as a replacement for my Powerwheels. (Not sure why the top gear isn't showing up in the customizer for me, but feel free to view the source and copy it to your own editor if you'd like). Hope it helps someone else.
Bottom Gear settings are the variables starting with the numbers 0 or 1 (eg. 01, 02, 10, 11, 12).
Top Gear settings are the variables starting with the number 2 (eg. 20, 21, 22)