Thank you for pointing to my error.
Subsequently, I tried again without setting the MY_REPEATER_FEATURE and ran into what seems like a radio communications problem. My program which cycles between a sleep() state and awake state with an interval of 20 seconds works for the one or two cycles, but then seems to get stuck when waking up.
In this stuck state the LED next to the reset button flashes at ~5hz, and the hardware reset button stops the flashing, but does not reset the program--it returns to the stuck state. Only cycling power to the Arduino resets to program.
The last radio communication received comes from the presentation() stage.
The loop() portion starts with a delay(timeMS) instruction where in the original case timeMS=20000. Experimenting with an timeMS<8000 causes no problem; however, for several timeMS >9000 the program gets stuck.
What is the cause of this behavior?