HELP. Problem with carry on mod with Ice and Fire mod

Well, I have a survival world with many mods including the ice and fire mod an the carry mod. Few days ago I discovered that tha carry on allow you to stack the mobs u are able to carry, i was experimentig with this and try to put a VILLAGER on a DRAGON, the villager just disappeared but since I was able to put him on cows horses i though it coud work in a small mob, I put a villager on a Hippogryph but i get on in too so i pressed shift and after that my game crashes. I tried to open it again but it crashes again. Is it possible to open a previous save of the world? (I dont know how to do that) or any other option?

Here the crash message:

The game crashed whilst ticking entity Error: java.lang.NullPointerException: Cannot invoke “” because “rider” is null

This isnt sponge related. May want to ask the devs of the mod that is failing