As a (free) game mods designer I can feel your pain.

    Couple years back I made a free add-on editor for a game called Operation Flashpoint.
Some German company decided to make a mission expansion pack (read commerical)
and used my editor to do so when I had placed a for NON-COMMERICAL use what so ever clause in the readme and legal texts.

    I contacted them and until I threatened to sue and had Codemasters backing me up did they say they would cough up a measly 1% royalties.

    I got one check, then suddenly their phone number and fax machine were
disconnected. Being in the US there was not a whole lot I could do about it.

    To make matters worse people started saying I sold out and yadda yadda yadda even
though the editor was still available for free!

There is an old saying, "Don't Look a Gift Horse In the Mouth"..... because he will bite your damn head off ;)

JD Wohlever
Techware 3D