[Mod Help?] Internal Server Error with Spawn Egg?

Whenever I make an Entity such as the Fireball or a Boat use a spawn egg by adding the numbers needed in the EntityList code, I get an Internal Server Error when trying to spawn the entity.Whenever I re-join the world, the entity is there though.This works with Mob Entities, the error only happens with entities like XPOrbs, Boats, Fireballs, EnderCrystals, etc.

Does anyone know how to fix this?I'm new to making regular-spawn eggs, so I'm not sure if another part of code is needed.