Hi again,
Since your problem also occurs when stepping, and you've found the attach to be not needed because it is still attached, I wonder if it still is attached. What happens if you attach once more after the file explorer actions?
You mention to '...
interact with file explorer using a separate BP object...', how do you do that today? Surely you already have a separate object for interfacing with the windows stuff? Can you list the steps you use?
Happy coding!
Paul, Sweden
(By all means, do not mark this as the best answer!)