howdy LCD and welcome to the forums!

when multiboxing wow, you will have to use /follow to get your alts to follow you around. you will not be able to keep the characters in sync using the keyboard for numerous (fairly detailed) reasons.

suffice it to say, you will need to have /follow macros. and since movement keys will break follow, you will want to put those in the DNP list.

after stating the obvious... there is something else. when you are driving along, normal movements and auto-run work just fine. but sometimes, when you are in a fight, you might want to drive all your characters at once... to say, strafe left or spread out. as such, you will want to leave one of the two sets of movement keys OFF your DNP list. this allows your some short distance driving... but you will find yourself needing to pull them all back together again using /follow.

i hope that helps.

Rob