This save is making to demonstrate the issue. Some other saves deleted earlier. The game is reinstalled so many times.
Other savegames saved when my u-boat is in open waters and there was no other vessel nearby. Same results.
And again: no matter whether have any enabled mod, or just the stock (v1.02) game version. If i want to load a "ship onboard" saved game, the results is a game freeze. Alltime.
