You attempted to add an entity to Mari0 that didn't exist before, right?
If you're using Vanilla Mari0, I suggest moving over to Mari0MS. It's a modding system that works a lot like Garrys Mod.
If not so, all I can say is:
The current Mari0 is 1.6 and is supported only by 0.8.0. If you have 1.6, you should be all good.
Last edited by HAPPYFACES on 21 May 2013, 05:20, edited 1 time in total.