I don't think we'll get a preview. I do think all 3 of those routes will have a little something though.
Ryan- During the photo shoot, F can allow D to take lewd photo's. This is similar to the last time, but D doesn't cover herself when she goes topless/naked or whatever it is.
Martin- No sexual sharing scenes, but we'll have a choice or two that progresses his path. Perhaps some light flirting and that sort of thing, if F/D allows it.
Graham/Olivia- No sharing scenes, but they'll call to reaffirm that F/D are ok with what happened. If they are, they agree to meet up again soon.
Kryptozoid
Thats an interesting idea with F/Martin/Elena. I've wondered before if the different routes will cross, I can see that one happening pretty easily.