[Bug][Beta1] Crash when Shipyard is distroyed

Hello,

Here is the series of events that caused the crash.  I had been moving my ship yard.  I anchored it when I saw an enemy ship coming near.  I clicked turn.  while I the turn was processing I entered the ship yard screen to see how close my next ship was to completion.  When I was inside the shipyard screen, a window popped up asking me if I would like to confirm battle.  I clicked yes (as there is no other option).  Immediately the game crashed back to windows.

I assume that the enemy ship I noticed actually attacked the shipyard while I was in the shipyard screen and the turn was processing. 

Hope this helps. 

-TheTraveler