I found an issue about instances in scene.
For example,I drag 4 treasure chest into scene.Then I preview.There are 1 to 3 chests would not create rewards.
But there are all right if the treasure chests are create by scene itsself.
That means if I did not set instance objcets into scene in advance.Treasure chest would be right.
I suppose this kind of issue comes from the instance in scene.Or I am not clear about the Basic instance rules of Constuct 3.
Could anyone tell me why the instances in scene layout won't running right rules ???