Update: The Beast Shield - Hotfix G - Version 1.5.1g for Minecraft 1.6.4
Hotfix F and G:
More Custom potion Effect Fixes: Ents and Trolls should no longer cause a crash when they are disabled.
Another small fix to the Custom potion Effects, the code is now based off of how Biomes O Plenty's custom potion effects code which is openly available on GitHub and is awesome!
Fixed a crashed caused when a mod tries to check if a creature is hostile or not from the client when the creature isn't fully initialized and spawned in the world.
Fixed the Custom potion Effects ID disabling and if a bad effect is applied, it will be removed from the entity, also any bad potion effects saved to a world (entity NBT) will be removed when loading, this should stop all problems all together and will fix worlds broken by this bug.
Added a Custom Potion Effects Setup debug option, this will print out extra info about custom effects.
Added Potion Effects ID override and a way to completely disable them if needed.