I'm having issues updating from 1.10 to 1.12. I have a world in 1.10 with GeographiCraft, RTG, and BoP, and I'm trying to update to 1.12 minus the RTG (which isn't done yet). Everything loads fine without GeographiCraft, but biomes are all weird- though all the terrain is the same (including colors), everything displays as being different biomes with different borders. I even used /locate, and it found an ocean monument in what the game claims is Deep Ocean but which was previously Desert, sand dunes and all.
When I add GeographiCraft, new worlds load fine and my superflat worlds load fine, but my actual Survival game crashes with this report regarding structure exceptions.