Character Blueprint Cannot Execute Montage to Play at a Negative Play Rate

While an Animation Montage can be played at a negative play rate in Persona, the user cannot use the Character Blueprint to execute this action.

1. Open attached project
2. Note that in the Event Graph of the Character Blueprint, P is set to play the Montage at a Positive Play Rate and L is set to play the Montage at a Negative Play Rate
3. Be sure that the Positive Montage play starts at the beginning (ie.0.1) and the Negative Montage play starts at the end of the Anim Sequence (ie.1.66) See attached image.
4. Play in Editor
   RESULT: Pressing "P" plays Montage at a forward play rate while Pressing "L" fails to play the Montage at a negative play rate
   EXPECTED: Pressing "L" to play the Montage at a negative play rate successfully