So, what's the deal w/this?
 

I've got a Black Sea campaign going, and I'm just south of the Kerch strait (?), and I've got a troop transport crippled very close to the shore. Whenever I fire a torpedo to finish it off, my game crashes. Anyone have any speculation as to why that might be?

You must be reloading a saved game each time after it crashes.
Sounds like you may have a corrupted save game

I've done that before. In which case, make a note of its position, reload your game, TC away from it for 30km, surface, make sure nothing is in range, save, quit, reload your new save, go back and destroy it.

- Edited for a typo

Okily!!

As it happens, this situation arose after TWO convoys (one passing each way through the strait) came through. Each had a troop ship I sank. :nope:

It's funny: if you look at Kerch on Google Earth, you'll see there is really only one channel VERY close to the city which could be used for deep draft vessels. Presuming things were about the same in March of '43, I don't think any Soviet ship would be passing through (save for the odd sub) as Kerch is still in German hands and would certainly have the guns to pwn anything in the near channel.