Here is a quick guide to baking out your normal maps from Zbrush into Marmoset Toolbag. Which worked for me.
A – If you are getting weird seams on your model in Marmo try these steps.
1 – Here are my multimap export settings for the normal map, its the same as the Maya export.
2 – Once the normal map has been baked, export your model using the “3D Print Exporter”
3 – Import your OBJ model into Maya, or any other 3D Package
4 – Unlock the normals
5 – Smooth the normals
6 – Export OBJ
7 – Import your model into Marmo, create and assign new material and import the normal map, here is my material setting
8 – Finally check the mesh is set to Marmoset Tangent Space
9 – Hopefully your normal map has imported correctly into Marmoset Toolbag