Basically, my map ended up placing the only Oil deposit so far away that I simply don't have enough Roboports to even reach it. I tried to use the Railbot, but I can't get the other stuff that I need to get placed, such as "get the bloody oil mining set up".

And without oil, I can't make outposts. So what do I do?

Nevermind, proceeded to carry a bunch of drones via a train, and then used Railbot's ability to place basic inserters to merry-chain at least one drone to the Roboport. Was fun, if a bit frustrating.

I probably need more documentation about strategies that are needed to make outposts work. But you have the right idea, Railbot is meant to provide expansion to new outposts with the ability to place rails and Roboports and few other basic items (which I need to document better).

For reference, here are the items Railbot can place if they are in the Buffer chest near the spawn:
"curved-rail", "straight-rail", "train-stop", "rail-chain-signal", "rail-signal", "big-electric-pole", "roboport", "inserter", & "logistic-chest-storage"