Hi Nsomnia](https://forums.unrealengine.com/member.php?29384-Nsomnia) well I receive this “missing influence” error because since MK skeleton have more bones, I guess some vertices of the Mk mesh were assigned to bones that I do not export.
In your case, have you try, before skin the character to the Hero Rig, delete all vertex groups on the mesh or at least the vertex groups that are not assigned to any Hero Rig Bones?
BTW, if you install the addon installing the zip file instead just the .py file, then you can press the button “Append hero” and is the same as open the template file included.
The error about Smothing groups, really I think is an issue on UE4 or side, I found how to avoid that error , and is export the FBX using “edge” for the Smothing option , but I think this is not ideal because if you have a split edges (double vertex) UE4 will merge the vertex, the addon use for the smothing groups “normal” ( in phyton that means OFF for smothing groups) because I found that I can import a mesh with any problems related to the smoth shading even if I have split vertex and some parts with smoth shading and some parts flat shading in same mesh using “normal”. If I’m wrong someone can correct me?
I hope that helps
Greetings!