Appreciate any feedback anyone has here.
Move a DIV.mktoFormCol inside a DIV.mktoFormRow and you have the standard 2-column layout.
So have a list of your ProgPro fields and go through 'em like this (pseudocode):
foreach field in fields, fromindex 1, step 2
append parent column of fields[thisindex] to parent row of fields[lastindex].
P.S. Actual code at MktoForms2 :: ProgPro 2up
The demo form config'd like so:
# of blank fields is 3 to show the dynamic 2-column layout (you'd probably want to show a multiple of 2 in production).