In this update I made a few changes to improve the plugin overall. The first thing I did was add support for custom banners and custom fireworks. The second thing I did was add the placeable field, this allows you to prevent players from placing custom items that are blocks. After that I added an update checker, if enabled, this will notify you when the plugin is first enabled if a new version is available for download. I also found a mistake I made in the first version that is now fixed. Also, please keep in mind that this is quite the large update and most updates in the future will not be of this size.
In both this and the first version of the plugin, you were able to omit the amount argument in the item get command, it would set "1" as the default. I forgot to add this to the item give command as well. That is now fixed...