Vanishing Issue With Updating Modded World 1.7.10 to 1.8

[NeonDiscovery]

I'm having a problem updating my modded world to 1.8. I run the mod Pixelmon with Custom NPCS. Everything but the Trainers carry over. For some reason the Trainers disappear.

 

The only thing I have to link it to is this. "forge mod loader detected that a backup level.dat is being used". This only happens AFTER I update it to 1.8. I don't get this message when I play it in 1.7.10. So for some reason it looks like the world corrupts when I try to bring it over to 1.8

 

I use the most recent forges before I update and after I update.

 

I saw this post a while back. Seems like they didn't find a soultion and ClientHax mentioned it being a forge issue. Hopefully this can be figured out.

 

http://www.pixelmonmod.com/tracker.php?p=4&t=6353

 

Thanks for reading.

[xAndrew77]

Ive been having the same issue. Someone please help or ive lost all my hard work!