Also, I found the code you mentioned earlier that tries to guess the Minecraft version:
https://github.com/tectonicus/tecton...ePack.java#L52
Question for you, T: Is your XML config pointed to the correct minecraft jar file? Check your line in the config starting with "minecraftJar". Is that the latest 1.9 jar? Using an older jar there might cause the initial rendering problem where it was failing on the dragon head.