—- I will just write the SOLUTION in place of my original post—-
In my case, when baking normals to low poly models in Blender, and subsequently importing the geometries (as OBJ) and maps (as PNG) in PreFab3D, I get weird artifacts. That is due to the fact that the normal maps are being handled differently by the two softwares.
A normal map in essence, is a RGB(A) image, where each individual channel contains specific information:
Blue channel - depth data (essentially a bump map)
Red channel - left to right deviation of normal
Green channel - top to bottom deviation of normal
A quick pit stop in Photoshop will fix the problem, you simply need to invert the Green channel.
Cheers 
