As long as you are following the instructions properly, I would say you have a defective board. This accessory is notorious for failing even brand new straight out of the box. In fact, they are so unreliable that most consignment game shops will not even consider purchasing them from you.
If you are simply finding it difficult to connect the board because you lack the proper instructions, here you go: How to sync Wii Tony Hawk Ride Skateboard (not my vid, but this is exactly what you need to do).
Well you may need to delete things off the memory to allow room for this game. On a Sony system it ask you off the start on Xbox as well didnt know Activision was even in business anymore