well...problem solved, i think.
having found a few other ctd threads in forum search - none of which mentioned my particular problem - i decided i really couldnt be ar5ed reinstalling and all that malarkey, so i just loaded the game and avoided doing the thing that had been causing the crashes...clicking on the last message id received. i just continued on my way, and, as luck would have it, i received a coupla new messages soon after - which i could access and read as normal.
the happy ending is this. about an hour of real time into the game my watch officer (hes already got an iron cross 2nd class, i swear im gonna give him a 1st class when we get home) spotted a ship at long range, in atrocious weather. i headed straight for it to make an ID and it was heading directly away from me. i didnt seem to be catching him that quickly, and a quick sonar check revealed he was indeed heading away at medium speed. even at flank i didnt have the absolute speed to "box" him unseen, so i just thought, bugger it, i'll charge straight up his backside. about 2 hours of realtime later, id got within a respectable range...and he started to zigzag, the swine!
this had an upside tho...it made me certain he was an enemy, so i just chased him down: tubes 1 and 4, fast speed, magnetic pistols set to 1.5m below his keel, 1.5degree spread, launched at 650m range...and a few seconds later, one detonated under his bow, the other amidships (man, my weapons officer is getting a medal too :p). british ore carrier, 8086t, my first kill of GWX2.1!
i love this game
so, like i said, problem apparently solved. i guess it must just have been a problem with that particular message...strange, but not game breaking. any thoughts would still be welcome tho
