Hey, this add-on doesn't come with any hotkeys currently. There is a button in the Properties Editor->Object Data->Shape Keys panel, which lets you switch from a shape key storage object back to the original object. You could probably right click that and choose Assign Shortcut.
Great addon, but which key do I press to toggle the view of the original mesh? It's blank in the "about" section for some reason. I need to do fine-tuning on an animated pose, and it's nearly impossible working from the T-pose mesh.