After months and months of trying to get the snorkel working I have finally succeeded
In both screenshots below read the text in the messagebox.
Even though it says engage electric engines the diesels were running at ahead flank @ 11m depth
I lowered the snorkel and the diesels shutdown and speed went back to ahead flank for submerged depth:
This was one way to make it work and not the preferred way. Now I'm going to make a new GR2 file for the snorkel and see what happens......