I can’t package game because of this error:
Ensure condition failed: ObservedKeyNames.Num() > 0
For last weak I tried to eliminate this with reviewing all my BTs - but when I alomost done it is started to appear unexpectedly - based on https://answers.unrealengine.com/questions/543765/cant-cook-content-for-windows-or-package-game.html - I tweaked all my decorators or cleaned up my BTs from them.
At this point my all BTs are striped to no nodes at all (It is worth mentioning that I get strange feeling, that this condition checked even unconnected nodes!) and this bug still appears.
After copying just BTs to clean project error no longer appears.
I’ve tried to delete data cache, intermediate and save folder - with no positive result.