Location for the first part of the dragon lord's quest appeared in the "wall" of Imperium (sic?). Though I could create a path to it, once my units got to the destination they just sat outside it, unable to enter. Quest locations need to ensure they treat the wall like it was water.
Another possible bug and probably unrelated, I killed everything in Imperium, as far as I can tell but still can not settle it as it says it's owned by someone else. After killing everything except for a single ogre, my ally came in a killed that ogre. Did that give them the location since they killed the last unit?