Ok, here's the version with Joey and Sophia in position.
To make Joey and Sophia stand out more, I desaturated the background a little bit - which in Flash means giving it a white tint of about 12%. I think that there'd probably be less need to desaturate the background in the actual animation, since the characters would pop out by virtue of being moving, but it's something that probably needs experimenting with at some point. But this works for now.