[GPK SS4] Please refresh my memory about Native vs. OpenRoads technology in SS4?

I'm back in PowerGeopak SS4, and it's been a few years...

As I recall, I need to develop my alignments (H & V) in the OpenRoads portion of the project, then export them to Native in order to be able to draw and annotate them for plans production. I also believe that I need to develop my corridor in the OpenRoads, then "export" my cross sections to a drawing in order to create sheets. But I'm not sure about any one of those steps...My SS4 experience and training was spotty at best, and most of that was for InRoads. Now that I'm back to Geopak, I'm second-guessing everything I thought I knew.

I was given a GPK file with my horizontal alignments, and I was able to import that into an alignment drawing, so I have OpenRoads alignments. At the moment, they are all in a single drawing...I think it might be better if I split them out to their own individual drawings so that different people can work on different portions of the project (One person doing side roads while someone else does Mainline1 and another does Mainline2). Or is that not going to work when it comes to modeling the different corridors to each other (Do they all need to be in the same drawing to be able to reference each other)?

How much of the design can we do with the native tools? And when I import Native back to OpenRoads, will it modify any geometry already there, or will it create additional geometry? Similarly, when we make adjustments in the OpenRoads technology and we need to export back to Native, does the information modify the existing COGO (etc.) or does it generate an extra set of geometry?

Do we have do do corridor modeling, or are we able to use criteria files? I'm capable in either, but I want to know what options might be available for all of our team members who aren't me.

I was looking through the Wiki and the on-demand training, but it seemed more efficient to just come here and ask.
Thank you.