Soul Silver pokewalker..?

Is the pokewalker mandatory to play the game? I could see them putting in some place where you have to use it, and without it you can't advance. Would be excellent AP, I so do hope it's just a useless addon.

No, it's not necessary to play the game.It's just an extra.not sure if you can use it with the rom though...

You can if your card is Wireless compatible. Bobykid used it and confirmed it on kazowars site.