Greetings, Joe.
I am using MH v1.2.0 running on Linux Mint Cinnamon 20.2 Uma. I downloaded all the body shape resources from your github page at the link that you have provided and then put them in the right places within the correct folders inside MH. They all show up as though all is well.
The plugin which calls them is active and the sliders are there under the tab specified. However, when a slider is moved, nothing happens to the model, which is the default base that loads when MH starts.
I can see how this will be a really nice addition once it is working properly. Thus, I shall leave it in there so that I can update it as your work progresses. In the mean time, a workaround is simply to use the targets inside the custom folder. There, they seem to work fine. This has me scratching my head since I am not a python guru.
I must give you thanks for all the hard work you have put into the community and the code which makes it all possible. Keep going. I shall follow your progress and share the results as best I can.