Error loading custom new chucks

[Thomas Loring]

Spigot username: Thomas_King Issue: So I've installed some custom biomes (http://discuss.dynamic-bytes.com/d/57-custom-terrain-biomes) Currently using version 1.8.8 of MC, and the corresponding EWG .jar Every time I load my new world and start to load new chunks, it crashes the server saying it's unable to load them, but sometimes I start the server again and join and the chunk is loaded it, until I leave to the next custom one. They're all displayed in console when loading up the server. Link to error log/crash log: https://pastebin.com/PbkQ3BzE Any help would be appreciated! Thanks, Thomas.