Add the following lines to your "Fallout4Custom.ini" file located in "Documents\My Games\Fallout4":

[Archive]
bInvalidateOlderFiles=1
sResourceDataDirsFinal=

1. Download and install via Nexus Mod Manager.
2. Activate the JaneBod.esp file.

To create your own custom shape:

1. Download and Install BodySlide.
2. The BodySlide files for this mod are located in a folder called Tools/BodySlide/...
3. Merge everything from that BodySlide folder into the same folder your BodySlide was installed.
4. When you load BodySlide there will be a new Body/Outfit option called JaneBod, select it then click Preview at the bottom.
5. Change the sliders to shape the body and then when you are done, click Build.