So I'm trying to play through the Dawn of the Galaxy scenario (Alpha 8.2). I went warping around, discovered Neo early, backtracked to progress the story. Now it's stuck on "Discover the planet Neo". I've gone and landed on Neo, left it again, went back to the previous sector, erased the playfields folder for Neo and Neo orbit. No matter what I try I can't seem to get it to progress anymore. Seems if something is discovered already it won't ever progress if the scenario wants you to discover it.
