I think I got it working today. Not sure what I was doing wrong before.

Also, you I recommend that you add the capability to pull different hunks out of the commit, and separate/unsquash them, or even move them to different branches. The UI is begging me to drag parts of the commit out. I can squash commits, but it doesn't seem like I can do the opposite.

Use Case: Just now I made a change to a config file, and a build tool also updated the version in this same config file. I want to split the change out.

Using the CLI to split the commit, I would do this:

  git add -p <file>.              # partial stage
  s                               # for each hunk

For splitting the hunk into a branch, I would do this:

  git checkout -b new-branch-name
  git reset HEAD^                 # if I already staged it
  git add -p
  s                               # for each hunk

Using Magit, splitting out the commit:

  M-x magit-status
  TAB                             # on the file diff
  s                               # per hunk
  e                               # when I need to refine it manually

Using Magit, to move hunks to a different branch:

  M-x magit-status
  TAB                             # on the file diff
  b c                             # new branch
  <same process as before>
  b b                             # as needed, switch branches

Again, want to thank you for you work here. It's really nice, I already am getting my team onboarded to it.