Martindale told BBC Scotland before kick-off that he wants five new players in - and five out - during January, with his focus on adding goals.
His one change from a heartening tussle with Celtic was up front, with Jeremy Bokila replacing Tete Yengi, but after this display, he will surely be looking to improve at both ends.
United counterpart Jim Goodwin was able to use his greater strength in depth by making four changes, with Iurie Iovu, Vicko Sevelj and Amar Fatah all perhaps unfortunate to drop the bench after impressing against Aberdeen last time out.
This time, it was Ferry's deliveries from the left and Naamo's late runs into the box from the right that had Livingston in constant bother.
Meanwhile, Sapsford will hope his eighth goal of the season and continuous threat up front will catch the eye of Australia head coach Tony Popovic in the run up to the World Cup.
While United are looking up - having leapfrogged Falkirk and Aberdeen into the top half - Livingston find themselves nine points behind third bottom St Mirren and with only Kilmarnock now in striking distance.