Quote from mr_hosed
Thanks on the TC4 stuff. Unfortunately I'm currently not in a place to spend time on 'em any further so here's a link to what I have done so far. Jolicraft TC4 Support v0.1
As for the "square" charcoal, yeah, that was actually intentional. I was originally going for a trianglur version of coal (kind of hint at burnt wood bits), but in the end I didn't want to spend much time with it and squaring off the big bits made charcoal look different enough to differentiate from coal, but still look Joliesque... sort of.
Yeah, I don't see a problem with the sprite you made.