It seems to be an ID conflict between Witchery and Enviromine. Both add a potioneffect with ID 36, but both have different effects. Solve the ID conflict and it should work.
Change the PotionID 36 of either Enviromine or Witchery to another potion ID that's not in use yet. I just did it by Trial and error and took potion ID 91 instead 36 from witcher i believe. So far i have no error, but i havent got into testing witchery yet, so there might be an error now.