%brick = MainBrickGroup.getObject(%i);
i feel like %brick is a brickgroup, not an actual brick
do another for loop similar to the first, to be more like
for(%a = 0; %a < MainBrickGroup.getCount(); %a++)
{
for(%b = 0; %b < MainBrickGroup.getObject(%a).getCount(); %b++)
{
%brick = MainBrickGroup.getObject(%a).getObject(%b);
}
}