Yes ... every other time that it is launched with [Broadcast Green Flag], the "Stop" button turns into a square. And when that occurs, the program does not run properly.
... After a forum search, I now see that when the "Stop" button turns into a square, it indicates that "When" blocks will not run. But why does launching with the [Broadcast Green Flag] block cause this to occur ... and why does it only occur every other launch?
... found a note from @BH that states
I am not sure how to avoid this condition, so that WHEN scripts will run when the game is launched.
Note: We plan to use MicroBlocks to send an "s" keypress when an arcade control button connected to a micro:bit is pressed. When this occurs, we would like to launch the game from a Raspberry Pi inside the arcade cabinet.