Model Engine Model Vanishes

If your ModelEngine model vanishes on a server restart, or when you leave the area the mob is in, you need to make sure the Model has the save attribute set to true

Your current mob file may have a line like the following:

Skills:
- model{m=Duck;n=name} @self ~onSpawn

While you can solve the issue by adding the following:

Skills:
- model{m=Duck;n=name;save=true} @self ~onSpawn