The story is rather long...
Lots of years ago Akella did the first Pirates game. It used STORM engine and had ABSOLUTELY the same graphics. The game was good as sea battles but the story was too short and many peopel started to create MODS...
Several years later Akella started to make a sequel... but at this time Disney launched Pirates of the Caribbean movie so they bought the ownership of the unfinished game and forced Akella to make "something" called at the same way... I say "something" because it was clearly unfinished and rushed game... actually this wasn't a new game but a super MOD for the previous game

But at the same time Akella was to blame too - they decided to modernize the STORM engine... Obviously they didn't knew what my grandmother always was saying - "The best way to destroy something good is to try to make it better". Because the only result from the modifying the STORM engine was the game started to crash:-( Of course the graphics remained the same... Besides this game was actually complete mess - as I said it actually was big MOD of the original with some stupid changes in it...
Couple of years later Akella decided to re-release Pirates of the Caribbeas (under another name - forgot the name) as it should be released if there wasn't Disney intervention. But the things got worse... It was completely bugged release with almost no story... AND THERE CAME THE AMATEURS...
They were the russian fans from the www.seaward.ru. They made super MOD for the game which was much better then the original. So after seeing this Akella made an agreement with them to make for them the "next" game - and they made City of the Lost ships. And of course the game is nothing more then the next super MOD for the very first game - with the exception of course because of crashes due to Akella messing with the original (read stable) STORM engine.
The truth is this the best MOD for the game... it has several story lines and offers lot to do.
But modding of the mod of the mod of the mod of the mod of a game made more then 10 year ago is not an easy task. Besides crashes (due to the negligence of Akella) there are lots of small glitches and the main fault - which I wrote earlier - they know everything about the game and made the MOD challenging to them, not thinking at all about the retail sales and the potential complete newbie players.