Both mods introduce milk, but the two forms are incompatible with each other. Any chance you could look up milk in the liquid dictionary before adding it?

I remember reading the code for the Forge FluidRegistry and it should make a lookup for a fluid when you register a new one, so it didn't make a duplicate. Maybe something changed in the new forge, or Automancy does something weird.

Checking that today.

Checked.
It is not this mod's fault, please inform Automagy's modder of the incompatibility.
He is registering a "fluidmilk" and/or looking for such a fluid. Looking at it, that milk fluid isn't properly set in the Fluid Registry, and creates some nasty effects on the environment when spilled with a bucket.

I tried looking for that particular fluid, but it isn't the same so my milk and that milk are different fluids.

Won't fix for the time being.