The scale should be in the form "x y z" so after hitting a brick:2 2 2
Would make your size double the width, length and height of any other player.0.5 0.5 0.5
Is half width/length/height.
1 1 10
Makes you ten times taller.
You have to be an admin to set scale change bricks with Aloshi's (in your own server, you are) and you can drive vehicles over them, or other players can walk on them to have their scale changed.