Hello! Thank you for your interest 
but that version is really outdated, it depended on CEGUI (pyCEGUI) and it was a mix between pycegui and qt4.
Please, use this mercurial repository as reference: p3deditor.googlecode.com
This contains the latest version which erased the dependency on pyCEGUI and works with pyQT and panda3d.
As you can see, pyQT is way more powerful, flexible and easy to set up on your installation (cegui needed a scratch compile). I’m recently back to work on this so there are possible updates in the near future
If you find malfunctioning and/or experience any problem feel free to reply to this thread or open a ticket on google code.
Thank you for your interest,
Claudio