Hello again! I tried to open the file. But my max is to old to make it. Now i am trying to replicate the scene by your description, with OSL Uber Bitmap Node.
I am not sure, but that what i have when i am open a maps i baked: Some maps i bake with Xnormals, some of them in Knald, some of them In MightyBake. And all of them has the same problem.