Can I sell RPGs I make with the OHRRPGCE?
From OHRRPGCE-Wiki
Yes. You can distribute your RPG files any way you choose, and that includes selling them. You can also redistribute GAME.EXE and OHRRPGCE.FNT along with your game so that people will be able to play (in fact, if you rename GAME.EXE so it has the same name as your .RPG file, then it will automatically load it without showing the file-select screen).
GAME.EXE is under the GPL license so you should be sure to include a link to http://HamsterRepublic.com/ohrrpgce/source.php in your README file.
The file LICENSE-binary.txt is included with the OHRRPGCE specifically for distributing with your game. It contains the full text of the GPL license, plus a header explaining that the game data can be under a different license.