This script creates a customizeable item scene that resembles the Pokémon games.
How does the bag scene work?
From the Bulbapedia page on Bag: http://bulbapedia.bulbagarden.net/wiki/Bag
The Bag appears as part of the start menu in all main series games, as well as in Pokémon Colosseum and Pokémon XD: Gale of Darkness. In Generation I as well as in Colosseum and XD, it is accessed with the “ITEMS” command, while in Generation II, it is accessed with the “PACK” command.
All items that the player has on hand will be located in the Bag and, after Generation I, being placed in the appropriate pocket automatically. Prior to Generation IV, the items pocket had only 20 (42 in FireRed and LeafGreen, 30 in Emerald) spaces for items, while the other pockets had space for any and all items that would go there. If an item to be picked up would be placed into the items pocket, however, and the pocket was full, it could not be picked up until the player had deposited some items into the PC. This problem no longer exists in Generation IV and beyond, where all pockets have enough space for every item.
Inside of the Bag menu, the player will find a list of all their items, ordered by default from the first kind obtained to the most recently obtained. Players may rearrange these items with the select button, except in the Berries and TMs and HMs pockets, which are automatically ordered. Depending on the type of item, and sometimes on the item itself, options exist when it is selected that allow players to use the item, throw the item away, register it on the Select/Y button for use on the field, or have a Pokémon hold it.
Script Download
http://crystalnoel42.wordpress.com/2013/07/28/crystal-engine-pokemon-bag/