I actually got it to work.
Here's what I did:
Under Edit in CSS Form builder I:
Added a new Group 4>Set 1>Field: 1>Type: File>Size: Small
Validation Required (unchecked)
Also note that when adding the file field/upload to the form it "*requires" a file to be attached even when under the form builder setting the Validation Required is unchecked. This is a bug.