I was just running into very similar issues and was able to sort things out thanks to this post and a few other Google searches. Some useful findings that might help others are:
- My character was using the wrong Skeletal Mesh - I had started with the “Third Person Tutorial” so my character was initially using the sk mesh named “SK_Mannequin” located in “Mannequin/Character/Mesh”. I pulled in the “AnimStarterPack” and created a new AnimBP copied from the “UE4ASP_Hero_TPP_BP” but failed to change my character’s mesh to the similarly named “SK_Mannequin” located instead inside of “AnimStarterPack/UE4_Mannequin/Mesh”.
- Blueprints let you pick the target for debugging but the window must be wide enough to see “Debug Filter” dropdown - I kept seeing that the BP flow was indicating that the pawn from “Try Get Pawn Owner” was not valid even though all of my connections seemed fine. I added some “Print Text” blocks to print the state of Valid and noticed that while running the game I’d see alternating “Pawn is valid” and “Pawn is not valid” messages. Turns out that the BP editor window was not wide enough to show the “Debug Filter” drop down that lets you change the target to attach to. Widening the window let me retarget to the “(spawned)” version of the AnimBP and sure enough the flow started indicating a valid pawn owner.