My bad then I thought you tried to have 0ad in google summer of code :/ /Offtopic.
EDIT : @LordGood I had a look at it. It doesn't seem feasible.If there is litterally anything we use in our meshes that is CC-BY-SA 3.0 when we put it on the marketplace it should be CC-BY-SA. And that can't work because Unity states that the end user has every right he wants on the model, which means he won't give attribution and it won't share it alike hereby breaking the license. Sad news for me I guess :/ @feneur