Hi there!
I don´t want to be a prick or anything but I guess all the demos are "Easy". If the demos where a little simplier, it would be difficult to use PMVC and Pipes because there wouldn´t be much to modulate.
Just read all the code, try to go debuggin it and tracing parts of the code and you´ll soon get it out figured. And most important off all, don´t give up!
Cheers!
ps: Have you read Josh´s excellent post ? Here´s the link:
http://www.joshuaostrom.com/2008/06/15/understanding-puremvc-pipes/