I've just found out that the anvil world storage is broken - it seems erratic, but it usually doesn't save chunk [*, 0] in the file. Or rather, it saves the chunk and then suddenly the chunk's not there again. Something keeps messing up the header. I'm not sure if it's my current code modifications, or it's been there for some time now.
Oh, it's not MCServer's fault as such, it saves the data ok, but whenever I run NBTExplorer on the file, it silently drops some chunks out, rewriting the file header. WTF??
Oh, it's not MCServer's fault as such, it saves the data ok, but whenever I run NBTExplorer on the file, it silently drops some chunks out, rewriting the file header. WTF??