Using the configuration changes from the plugin page, I added the .egg file to the plugins directory, Trac 0.12.4.
https://scm.escience.rpi.edu/trac/ticket/1313
I created a child ticket https://scm.escience.rpi.edu/trac/ticket/1314, and specified #1313 as the parent ticket in the Parent ID field.
When I go back to 1313 I get nothing. I also don't see any reference to the childtickets.css file in the html source. It's picking up the new Parent ID field, but that's about it. I don't see any other configuration information, and there's no README, or INSTALL file in the egg or in the downloaded .zip file. I'm not sure if I've installed it correctly, that it's enabled correctly, or configured correctly. Any help would be greatly appreciated.