For the "retrieve from reserve" function to work, you need to first place the corresponding hero in the reserve. This is done in the editor in the properties menu, I think on the players tab.
I found this, but my map isn't in the AdvMapHero menu.
Added 3 minutes later
More precisely, I clicked on ReserveHeroes and a menu appeared with the AdvMapHero tab (there are DialogScenes, Maps, Test there), and my map doesn't appear in Maps/SingleMission.
