Adjust the Labia Morph Min sliders to set your preference when the legs are closed.
Then adjust the Labia Morph Max sliders to set your preference when the legs are wide apart.
The labia spread will then auto-adjust according to the degree the legs are spaced apart.
The top two sliders are for the legacy morph which maintains compatability with scenes made with previous versions.
They control the overall 'gape' of the vagina. Fine adjustments to the labia spread can be made using the remainder.
Which is all this plugin emulates. Any labia style morphs really should be applied prior to setting up this plugin.