I realize that it's been awhile since you've heard anything about PRP Explorer (well, other than version 0.7 likes to eat your PRPs...). After quite a bit of thinking, I thought that instead of just letting the code go to waste, that it would be benificial to all to open source it. So, the result is the immediate opening of the formerly private PRP Explorer subversion.
Before you cheer hallejulah to your Deity of choice (or just say "YESS!" because you don't have/don't think your Deity has any influence), I'd like to tell you a bit about the history of PRP Explorer.
PRP Explorer not the first tool that was able to manipulate the PRP Files. There were some command line utilities that would read the PRPs and extract each object from them. PRP Explorer was the first to go beyond that, however, and provide a means to edit the objects without extracting them. It was written as a quick "proof-of-concept" to tinker with the files and see what did what: in other words, it was something quick to double check understanding. After that understanding was gained, PRPExplorer was to be left to rot. Yet, it has still survived to the present day due to several people who began writing PRPEx and those early tools. So, what does this mean for you? The PRP Explorer code is: UGLY and Not very easily extended.
Now, for a bit of new news, PRP Explorer 0.7 has been labeled unstable. The latest code in the trunk is of a new version: 0.8. PRP Explorer 0.8 is based off of PRP Explorer 0.6, so it shouldn't have the issues that PRP Explorer 0.7 SATAN did; however, this also means that many of the advanced features from 0.7 are missing as well. I have begun replacing those features myself, but right now, I lack the time to rewrite everything myself.
The PRP Explorer Trac is located at: http://trac.hoikas.com/prpex
The PRP Explorer SVN is located at: http://svn.hoikas.com/PRPExplorer
Please not that you cannot write to the PRP Explorer SVN anonymously. I will have to grant you access to do that. Please contact me if you're interested. If you have a patch for the code and don't have write access (yet), then you can submit it via the Trac Tickets.