Bravo Zulu, that works!
All I wanted was to move the Asiatic career starting point from Manila to Cavite but couldn't see the Cavite docks in the mission editor. Correct way to start would be to anchor a sub tender near the docks with a nest of subs tied alongside, possibly with the player sub just outboard of the last one. If I can get that to work I might try adding new docks at Corregidor and Subic Bay.