Geared Heart - Modified parts

I wanted to print the 1-2 version of the geared heart, crank edition : http://www.thingiverse.com/thing:253934

There was no center part for the 1-2 version yet, so I tried to create the centerpart myself. This now seems to be correct.
The existing gears did not seem to work for the 1-2 version, so I tried to modify them until they do. They seem to be working a little bit, but there is too much force required by the looks of it.

Maybe the 1-2 version of the geared heart requires too much f