I made a villager with custom trades, holding items with attributes, coloured nametags, big enchantments, random words (§k) etc.

When I try to trade with it, it seems to crash and I think the villager was mad because I hit it a lot.

Sometimes, it gives me a corrupted save file when I try to trade with it, eliminating the level.dat or damaging any other property of the world.
The world is still in the saves folder but doesn't show up in the Worlds Selection.

The villager was created from a schematic file which I made from McEDIT.

I hope you fix it, because it corrupted a project I was making in singleplayer.