In this update, I fixed a few common bugs with the plugin, including:

- Players having the ability to make slab shops on upper and full slab blocks (now only limited to lower slabs).
- Console error when attempting to send vendor message due to invalid cast from OfflinePlayer.
- Console error when attempting to purge shops that are not in the same world as the command sender.
- unnamed items not displaying properly in chat on purchase.

NOTE:
I have not been able to replicate a bug which has been mentioned twice in which players suddenly can pick up display items. Under normal circumstances, on a test server with no other plugins, this is impossible. If you experience this issue please contact me immediately and further explain the circumstances of the incident as well as the plugins you have installed on your server. Thank you.