I'm not repairing

[-Pv-]

To reapair the flak gun and cannon,You HAVE to have a crew member assigned to the gun and ACTIVATED. As soon as the gun is repaired, remove the crew member or they will get injured when the gun breaks again 15 minutes later.
No repairs to the guns will be made if there is no crew assigned and ACTIVATED.
The dedicated repair crew will not repair the deck gun or flak gun. As far as the entenae, not sure. Move injured crew to other non-damaged compartments and place them in sleep mode by moving them one shift foward in the crew rotation. Injured crew do not repair very well.

"Known bug with the Deck/Guns. They can't be permanently repaired. Oh, and anyone you leave on the Deck will eventually die. Have fun~! "

There are two identified items with crew deaths that can be worked around. Your deck crew is not doomed.
1) As I have mentioned above, remove crew assigned to the flak gun. It gets re-damaged every 15 minutes and each time it does, your assigned crew (active or not) gets increasingly injured. Your watch crew is not affected.
2) Do not save and restore a game within 10 minutes of in IMPENDING crew watch change. Save the game after the change. If a watch change is due to occur within 10 minutes of a game restore, your active crew will have their health subtracted.
-Pv-