Hey Freaknstein, thanks for your kind words!
Do you have the latest update installed. There was an issue with previous versions where medals did not work properly.
In general, that's what you need:
Every medal counts only for one patrol (Midway - Patrol - Midway).
Navy Cross: 4 freighters
Bronze Star: 2 freighters and 2 tankers
Purple Heart: 2 destroyers and 1 freighter
Navy Commendation: 1 light cruiser, 1 destroyer and 1 freighter
Asiatic Pacific Campain: 1 carrier, 1 freighter and 1 tanker
Combat Insignia: 2 gunboats and 1 destroyer
Legion of Merrit: 2 carrier and 1 troop transport
Medal of Honor: 1 battleship, 2 destroyers and 1 troop transport
You don't get medals post mortem.