When you start the game up, you get given a Pokémon egg which contains a Pokémon knowing a certain attack. It is unsure if you can only get this once but it is worth it.
Pokémon Box Eggs
Anyway. here are a Few Screenshots with explanations explaining the various functions of this expansion pack:
Storage Box Here there are 25 boxes to store your Pokémon from the games in. Each box contains 60 pokémon in them. That means that you can store up to 1500 Pokémon on this storage box utility
Pokémon Stats
Here you can view the two pages of statistics for the Pokémon. The first page containing the attacks, stats and other information. The second page contains the contest information. Like how high the Pokémon's beauty is (as seen in the PokéNav) and the type of the attacks which the Pokémon has and what they do in the contests.
Pokémon Figures
A Common thing recently in Nintendo games, here you will have multiple figures of each of your Pokémon that are stored in. You are able to arrange them and make your favourite Pokémon stand taller than the others
Pokémon Emulator
Like the Stadium games on the N64, here you have the chance to play Pokémon Ruby & Sapphire on the TV screen