Working Jack Sparrow Gangplank
Looking at the files of SizorBlade's Jack Sparrow skin, I found the problem that didn't let the skin work properly.
The problem isn't that the skin is too old for the game, but when Riot made the Gangplank rework it changed the champion's file name from "Pirate" to "Gankplank".
Now I have changed the names of all the files and reuploaded them here :D
I have tested it only with LGG's skin installer and it works. Jack Sparrow seems a bit small, but I'm not the creator of the skin and I don't know how to create/modify one :(
Credits go to SizorBlade who made this skin.