What you are doing here is clearly not ok, and I feel slighted by the whole thing. You have taken my code, which was made available to you under the condition that all changes must be shared alike in the same fashion -- and have violated this agreement, and ignored my attempts to have it remedied.
I have deep respect for your contribution, and I am considering it. For now I'm holding of since you're selling it yourself and I'm very uncertain about the new owners. Please allow me this time (it's not even 24 hours online yet).
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And let me say once more that I haven't ruled out open sourcing the site or parts of it.
You don't get to decide whether to "open source" it or not. The project is already open sourced. You get to either share your changes or be in violation of the license you accepted by using the code.
I've left you negative trust linked to this post, and will remove it if you take steps to comply with the code's license.
Which is sad, considering he did make the game look very slick.