When creating the offset, does it help to add a few vertices to the mesh?
For example at the corners of the mouth or eyes (might need a denser mesh more often) or if you need a crease at a specific location, or are they readjusted to the original mesh when exporting?!
Comments
The way it works is this - the basis shape is used as a "key" to create a translation between fvne mesh and authored offsets. For every vertex in fvne mesh, there will be a corresponding index in the authored offsets. If there's extra vertices, they will simply be ignored as only the closest vertex to each vertex in basis will be used.