(watch last 4 min of video)(ignore stuff said by Tim)
When you are making a rig it is important to reference the geometry and not import it into your scene. This is because when you are transferring attributes such as UV's you can go into the plain geo file and delete the history. This should stop your blendshapes from lagging however, you will have to remake the shapes in the shape editor.
When exporting the file be sure to export it as an obj. This will allow you to create groups in the file for the eyes, claws, toes, etc...
Once in the obj file be sure that the geo is grouped together and that it the gimbal is located at 000 on the Grid. Make sure that there is only one group and that everything else except the geo is deleted. Make sure that empty groups are deleted.
Image (geometry will go black sometimes, this is normal)
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