Early in the episode, the Nazis are shown driving a vehicle with right hand drive while escaping with the gold - but all vehicles driven in Germany (even during World War II) have always been left hand drive.
The information on the microdot and the watch glasses supposedly have been made in 1945. However, one of the gravestones the solution connects with each other shows that the person buried there died only in 1977.
It's not uncommon to pre-place a headstone on a purchased plot with the date of death left blank, to be added after death. The future occupant did so prior to 1945.
The watch crystals logically need to be aligned to form the map. Graff just drops the crystals onto the stack, making no attempt to line them up.