Today I bring a huge update to the plugin, changing the overall appearance of the plugin and how add/remove items is handle. Now all is done from in-game GUIs, items.yml can be now deleted. This was necessary, it allows to bring support for every item (custom textures, MMOItems...) and get rid of the pain in the ass of working with yml.
WIth this i'm confidence that the plugin i now out of beta.
Finally, I recommend to remove everything from the plugins folder and let it regenerate the resources