The Sinking City 2 Salt Storage code

The Sinking City 2 salt storage code opens a strange lock in the Fish Market once you work out what the roman numerals mean, as well as how they tie into a 16 Punishments of the Sailor note you can find. The solution is not that hard once you have all the pieces in front of you, but it is one of the slightly tricker puzzles thanks to the numbering system and a long list you need to work though to decode it all. Here's what I did and how I solved it so you can get in. It's worth doing too as ther