I use RUB, not GWX, so pretty much like stock, and Harbor Traffic 1.47 to give me some ships in ports.
I used SH3 Commander to set my max TC rate to 2048. This works OK, although my ancient computer can only effectively handle this rate some of the time.
I had one Kaleun who made a harbour raid on nearly every patrol. In Scapa Flow he got an aircraft carrier and an auxilliary cruiser. Elsewhere, no warship bigger than a DD. Over all he got nearly 300,000 tons. Then he died.
He used mag shots 2m below keel on capital ships, usually impact on DDs. Doesn't seem to matter much where you hit a DD. Hit it and it sinks. On large immobile ships, aim below turrets, or stacks, to hit magazines or engine rooms. Allow at least three torpedos per capital ship. You will probably need more.
All infiltration, attacks and exfiltration were done submerged at <= 2knots. For the Scapa raid, he found a far corner to surface and recharge at night. Didn't see any mines. When nets were encountered, ran parallel until a gap was found.
Don't wait to install SH3 Commander. Do it now!
In Berlin I prefer the Kurfürstendamm. In Kiel it depends on what sort of fraulein you are looking for
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