I have a beta 1.2 SMP nether world that has been upgraded to 1.3 that will not render with c10t mapper. I don't believe it ever actually rendered when it was a 1.2 world either, so this is not a new issue. I have no issues logging into the world or with making modifications to it; it acts like a normal world. However, c10t doesn't seem to find anything to render.
I have a beta 1.2 SMP nether world that has been upgraded to 1.3 that will not render with c10t mapper. I don't believe it ever actually rendered when it was a 1.2 world either, so this is not a new issue. I have no issues logging into the world or with making modifications to it; it acts like a normal world. However, c10t doesn't seem to find anything to render.
I've placed a copy of the world at: http://files.empiresheep.org/blacksheep/nether.tar.gz
Current version tested: git 507b27b
Here is the error(?):