I'm gonna wait for Steam version
Free work is ok if it's not-commercical project, such as modding for game. If it's commercical and they're going to make money off your work then it's unfair.
Doko Roko Trailer
A trailer for the2D rogue-like vertical action game Doko Roko. In this project players will have to fight their way through the ruins of an ancient tower. Gamers will collect spells to battle hostile creatures which live in the Tower. They will also have to forge swords to battle their enemies. The world of the Tower is procedurally generated filled with libraries, grimoires and stone obelisks.
© Eric Mack 2015, YouTube Link