Hello, 
I am able to export the CC3 Pipeline base character to blender, then use blender sculpting tools to modify the body, but when I try to import the character back to CC3 pipeline, I get a load fail. 

I am using only a multiresolution modifier in blender, I do not apply the modifier, just use the apply to base option, before exporting to fbx. 
I am turning off the leaf bone in the blender fbx export. 

Or does CC3 pipeline not allow creating a replacement body mesh using Blender?  If CC3 pipeline does not allow this, then which Reallusion product do I need to allow me to export a base model to blender and import it back so that I keep the armature and mesh. 

Thanks in advance

There are specific Blender settings required. I don't use this option, so somebody will hopefully enlighten you. But you should be able to sculpt the mesh as long as vertex order and count are maintained.

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