I will have to try this
EDIT: Quitting the game out to the dashboard and restarting entire game fixed the issue. Annoying but a relief. Hopefully gets patched soon...
This is happening to me as well. I used one maneuver node to get into orbit, but now it won't let me select any point in my orbit to make a second maneuver. Poor Jebediah is stuck around Kerbal and I don't want to "eyeball" it!