Great work so far Cees! Good to see you've picked up one of Fokker's less successful designs.
Found a photo of the three prototypes which show three different engines, three different landing gear configs and at least two different wing configs!
One was designed with a Jaguar engine for Italy but ended up in Manchuria of all places, the second prototype had a Bristol jupiter engine and was sold to Hungary who ordered another three aircraft.
The last one had the 625 hp Curtiss Conqueror and was built for the LA-KNIL but after the prototype crashed no aircraft was ordered. The Dutch LVA did order the D.XVI, but with the Jaguar engine. Fourteen were ordered, and registered 275-288. Vijf crashed within a short time span, and other suffered from engine failures so the aircraft was restricted to a limited range away from the field. Reducing the diameter of the pistons a bit helped to solve the engine problem, but increased the oil consumption limiting the endurance of the aircraft to 1.5 hours while it could carry enough fuel for 3 hour! On may 10th 1940 only the 277 was still operational, flying with the 'jachtvliegschool' at De Vlijt and was captured intact by the Germans.