I have setup a Multipage Group with thee multipages. I am trying to figure out if there is a button to save a draft while working on the form and autosave a draft when moving between pages. Some of the fields that I have on the form are essay questions for the user to answer about themselves. So, it would be really nice to allow them to save the essay and come back later to finish.
If this functionality is not currently available. I would highly recommend doing something similar to how the webform module allows users to save a draft before they get to the last page and hit the submit button.
I am willing to pay someone to add this functionality and contribute it back to the community. I need it in the next two of weeks if you're interested.