Yeah you see the workflow action to create a new form, add another workflow action which will be to
Modify a thing (Do a search All forms:user =current user) then add result of step one with an only when condition that current user All forms is not empty…
Another workflow action this time around with the only when current user All forms empty, now you “set list” of result of step one and not "add list " as in the prev. action.
Note in the DB you must have linked FORM(list) to ALL FORM data type for this approach to work…
I hope you get it