ye'd be much better off using the open source D20 clauses and publishing the entire setting 1st as a PnP campaign set under your own publishing company before you consider going digital release via 3rd party. The very second you let a gaming company get it's grubby little hands on your setting, some suit struts in from the marketing office with "high impact" changes to sell the "product". I could just see it now...
"Great setting, great! Me and the boys were marvelling at how this will be the best seller of the 4th quarter! Buuuut... we'd like to change a few things..."
L-what kind of things?
"Well, does it *have* to be called "Layonara?" I mean, that sounds like "goodbye" in japanese... what's that word... ah yes! Sashami! We were thinking something more current, more NOW... Like "Dr. Dre's Ho House of Horror!"
L-but there is no Dre in my setting...
"That's another thing we've been meaning to talk about. This Ozymandius... nobody likes Ozzy anymore! since the ratings dive of his reality TV show on MTV, we feel we need a fresher face. You know, a bard that helps the player out with the power of Hip Hop! *does a retarded little marketer dance and starts singing* 'it's like this and like that and like this and uh.. UH UH! YEAAAAAHH, smoke dat dragon mofo!"
L- *sounds of forehead slamming into the table*
"Oh, and speaking of music, to sell this thing, we really need our own custom soundtrack... something nobody's heard before! Let's get Billboard to sell us the liscensing to their top 40 for exposure! I was thinking Gwen sining here 'Im just a girl' song would make an excellent intro! And imagine the battle scenes pumping with that "Rolling rolling rolling" song by that Durst fellow... oh yeah!"
L-look, I really don't think...
"THINK?! We don't pay you to THINK! We pay you so we can own your vision, nothing more! This name on the dotted line means we can do anything and everything we want to make this game a blockbuster! Oh, and we need to sell toys. How do you think the kids would like it if we dressed this Duur fellow up in gold chains, a feather hat and gave him a CaRAAAZY foreign accent? eh? eh?! We can get Leanoardo Dicrappio to do the voice acting and give him, I dunno... purple neon fur? Kid's be begging for 2 billion by christmas!"
L-*opens fire and destroys all at the board room meeting mercilessly, before storming off into the downtown sprawl all post-office like*