Hi Slayemin,
I don’t believe this is a bug, though I may be misunderstanding your setup and result from it. If you run a Service before key is set, as Breyarte explains in his workflow below, I would expect Selector to to fail.
As I said, I may not understand fully what you’re describing, however. If you can post some images of your BT and BTS graphs, as well as any other pertinent graphs from Tasks or Decorators below, I can run through it and see if this is expected or if there’s a bug in there. Thanks!