I had previously opened up a report regarding this mash-up/world loading up as a vanilla survival world. I am aware that you had 'resolved' this problem, however, when I am launching this world, I am being prevented from making/entering these worlds for no absolute reason besides an 'error'. I had attempted restarting Minecraft, redownloading Minecraft, and redownloading Mod, and nothing else is working, so it seems from my perspective that this isn't coming from my computer. It would be appreciated if you can look into this!