In the Comments section, someone wrote
the Germans shipped a Panzer Army to North Africa <snip> and supplied it by land via Gibraltar while attacking Alexandria and Cairo <snip>
I would have written this reply there, but it doesn't appear one can reply in the Comments section.
I want to clarify that as I think they played this rule incorrectly. The Germans cannot give Full Supply to any German unit in Africa or the Mid-East via a Land Supply Line except through Russia and then Turkey.
To provide Full Supply via a Land Supply Line, the Transportation Line being using must be contiguous back to a Supply Source in the Home Country, in this case Germany. The rail line at Gibraltar and at Istanbul do not cross the Straits there. Therefore, you cannot trace across them.
As for the rest of the comment, it was their opinion and I won't dispute it. I just want to point out a rules error.