Are runners and cyclists supposed to push the button(s) to turn on the yellow flashing caution lights along Rt 27 before crossing the road? So many don't do this and cycle right onto the road and expect drivers to stop, sometimes very quickly.

"supposed to" is subjective. If you were walking and then crossing an intersection I would think you would definitely stop for traffic. I would think bicycle riders should do the same. Otherwise as you pointed out this certainly can be a safety problem!

I recommend you do.i di it.its a long trail

The lights change as needed. We never had to power up anything. T