Hi Kathy, Scout suggested I go ahead and post my solution to your query. Here's a pic of what my result looks like.
As MF & scout had asked, I, too, thought that the crown would likely curve from the point where the cul-de-sac begins to it's radius point. To achieve this, I created a new alignment "FG-crown" that follows the FG(1) alignment until the point of curvature, then curves the the left to the RP. I then created a profile, superimposed the FG(1) Finish grade profile to it, and created a new FG-Crown FG profile. For the actual crown profile through the new curve I just held the elevations of the original FG profile at the BC & RP for a straight grade between the two. This is easily altered if desired.
I then added BasicLaneTransition subassemblies the 2 partial assemblies. The width & slope do not matter since I set the transition toggle to "Change ofset and Elevation". Next up I added an alignment, using the TIN lines of the surface, along the assumed EOP, and created a profile of the EG from the surface (I didn't need to see this so I didn't add a ProfileView). I also made sure all of the Daylight slopes used the same params.
Finally I edited the Corridor properties. First I edited the Bulb region to set the targets for the LaneTransition to the FG-Crown alignment & Profile. For the 2 curb returns I Split them, using the intersection of the EOP alignment with the FG(1) alignment as the split point (you cannot snap to this, so a zoomed in eyeball pick works for this). Now I set the targets for first region of each return to be the EOP alignment & EG profile, for the second region of each I used my FG(1) alignment and FG profile as the targets. Lastly I used the Set All Targets to set the EG as the target for the daylights. Note that the ditches are funky at the curb returns, this comes from those portions being in a Fill condition,m whereas the remainder of the corridor is in Cut. ALso note that the daylighs fail at the end of the cul-de-sac due to the surface not completely covering this area.
There are other ways, I'm sure, to do this, but this is pretty much what I've used for some time now. One thing I would like to mention, and others may have something to say about this, too, is that ALL of my curb returns I define in the same direction. IOW, all curves curve to the right. The begin & end stations do not matter, but it allows me to use just 1 Assembly (aptly named Base Curb Return) for all of my returns.
I hope this helps to clarify things. If you still get stuck & you'd like to use the drawing, just say so & I will post it.