Sounds strange
And even stranger if you take into account that in GWX 2.1 I've sunk a coastal tanker, a large merchant, a tramp steamer and an ore carrier so far, and they all went down without hiccups. The tanker was sunk in AN14 and the rest in AN26 IIRC - at work ATM so cannot verify...
So maybe it really is the zones.cfg then, aye
