I encountered the following problem using DA in 4.22. I tried to create a new Grid Builder by pressing the + sign next to the Grid Builder property on a dungeon I created. It asked me for the name and where to save the file to. Then when it tried to create it, UE crashed and gave me this error.
Unhandled exception
UE4Editor_DungeonArchitectRuntime!ADungeon::CreateBuilderInstance() [d:\build++portal+dev-marketplace+full\sync\localbuilds\plugintemp\hostproject\plugins\dungeonarchitect\source\dungeonarchitectruntime\private\core\dungeon.cpp:276]
UE4Editor_DungeonArchitectRuntime!ADungeon::PostEditChangeProperty() [d:\build++portal+dev-marketplace+full\sync\localbuilds\plugintemp\hostproject\plugins\dungeonarchitect\source\dungeonarchitectruntime\private\core\dungeon.cpp:189]
I was able to create a Custom Grid Builder by creating a new Blueprint and selecting Custom Grid Builder however so it’s not a big deal. Just giving you a heads up.