[instakill]

Impossible to add the chains with a touchpad.

[frankl]

Using it with a touchpad is far from ideal, but you should be able to manage it by drawing the chain very widely around the gears. The chain will be tightened automatically.

[bherms]

You need to create two gears, a big one and a small one, then place the small one directly in the center of the big one. You can then attach a chain around a gear. Took me forever.

[matthuggins]

Same problem on my Galaxy Nexus, I tried all combinations of placing a belt, and it just wouldn't work.