I'm still not clear as whether their license would allow me to distribute a texture made with their content under a CC license. But this is not relevant for me anymore, as I am no longer distributing any textures with the Antonia base package.

I see that BluEcho has already started a thread about this in the copyright laws and ethical standards forum (right at the bottom of the forums list, for those who've never seen it). I strongly suggest that anyone interested in further copyright and licensing discussions goes there.

-- I'm not mad at you, just Westphalian.