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1:
G&W can pull his usual Nair through the platform trick on this transition. The size of this stage is very small, which allows G&W to apply constant pressure on his opponent. I usually play aggressively and offensively with G&W on this part. It keeps the pressure on your opponent and since the stage is so small, he has no where to run. On larger stages, your opponent can just run away and reassess the situation after he just got 75% in 15 seconds without being able to touch you, but in this stage, he has no where to run. If you play aggressively on this stage, you might be able to exploit the "shock factor" and take advantage of your opponent that way, but most pros are able to remain calm, so it really depends on the player himself.
This stage has a lip on both sides, so just aim for the edge and you won't get stuck under the lip.
2:
This is the walkoff transition with breakable statues. We all know attack the statues will refresh your moveset. The statues usually interfere with projectiles users, so they don't really hurt G&W. Just be careful not to stale out your kill moves by whiffing your opponent and hitting the statues instead.
This stage is really big and the platforms are really high and spaced apart. G&W will have a hard time exploiting the platforms like he usually does. They are also too big to take advantage of techchasing.
I don't really like the transition, no matter what character I play.
3:
Nothing special here. It's almost like BF without the platforms. I believe the stage tilts a little, but that shouldn't throw you off too much.
Transition phase (the grey part):
Ahh...I like this part. When it transitions from 3 -> 1, try to hit your opponent to the right. This is really effective against people with sucky recoveries. I once grabbed an Ike during the transition phase and after the stage transformed to the first part, we were floating way out there (on the far right side of the first stage, off the stage), and I was able to make it back, but ike wasn't...GIMP!