Ripplin said:
And this is all I can show, because who knows how far it went?:

Haha.

Seriously, is that just Mark and Carrie goofing around, or was it a proposed scene, or what?

I'm not sure, but on the Editdroid bonus disc 3, the 1979 teaser trailer #2 shows a different scene of them going for a smooch. It looks to be during the scene where she kisses him in front of Han and Chewie while he's recovering, but it's a totally different shot, as they are gazing longingly into each other's eyes as they move for the kiss. It freaked my girlfriend out when I showed her the trailer a while back. Kind of makes me wonder where Lucas was going with that idea.