Can I make my own version of the OHRRPGCE?
Yes. The source code of the OHRRPGCE is available, and as long as you comply with the terms of the GPL license, you can make your own versions of it. You should start by reading about the source code
A Few Words on Nomenclature[edit]
If you make a new version of the OHRRPGCE, you must be careful what you call it. If you simply want to add a new feature that is not present in the official version, you may continue to call it the OHRRPGCE, since that is what it is.
However, if you want to take the source code and make your own seprate project, and split away from the OHRRPGCE, you cannot call it the OHRRPGCE any more. The phrase "Offical Hamster Republic RPG Creation Engine" and its abbreviation, "OHRRPGCE" are a trademark of Hamster Republic Productions. Further, a seprate project won't be 'Official', so that won't even make any sense.
Finally, while the name "Unofficial Hamster Republic etc." (UHR) may seem clever at first... Just don't.
A Few Words on New Features[edit]
If you add new features to your custom version, consider making a patch of the changes and submitting them to us to include in the official version. I'm sure that people other than yourself would like to use those features, and you could go down in history as 'the guy who made suchandsuch, whosisname!'
On the other hand, if you're creating a rival project, we'll do our best to grind you into the dust (kidding).
A Few Words on the GPL[edit]
If you make your own version of the OHR, it must be under the terms of the GPL as well. It says so in the GPL. The only way the OHRRPGCE could be un-GPL'ed and relicensed under some other terms is with the unanimous consent of all OHRRPGCE developers. (not just James Paige, but everyone who has contributed code)
Secondly, any new code you write for your new version must also be under the GPL license. The GPL says that too. And, if you copy snippits of code from the OHR to a seprate project, that project must also be GPL'd.
Actually, just read the GPL. It'll be easier for both of us.