Blueprints containing child actor components that are overlapping in the blueprint's viewport cannot be used as the default pawn, as they are not spawned in. Using the Spawn Actor From Class node works because you can set the spawn override to spawn regardless of whether or not it is colliding.
Found in 4.10.4 binary. Reproduced in 4.11 Preview 6 binary and Main CL 2894512
Test Project Attached
1. Open the attached project
3. Notice that the pawn is not spawned, even though it is set to the Default Pawn in the game mode.
4. Go into the MyPawn blueprint
5. In the viewport, separate the child actor components so they are not overlapping
Result: The pawn would not spawn when the child actor components were overlapping, but once the child actor components were no longer overlapping, the pawn spawned as expected.
Expected: The pawn would spawn even though the components were overlapping.
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