The rest was all the defaults except that you have to provide an assertion. They may use the WS-Federation terminology when talking to you and call it a claim. But I had to create an Attribute Statement: Name: AccountClaim Name Format: Unspecified Value: user.email
Wanted to make sure anyone else going through this doesn't have as much of a struggle as I did. You will also have to tell M-Files that the name of the "Claim" is AccountClaim so M-Files can update a registry item on their side.
Once you get it all working, make sure you remind M-Files to "persist" the change or you'll have to go through it again when M-Files reboots/patches their servers.