So I now have my RP3+ and I used Etcher to install the RP Stretcher from 2017-11-29. However when I turn on the RP3+, I just get the multicolor screen and the board has a blinking Green LED in some pattern. Did I miss a step? I just downloaded the .zip file for Stretcher, Flashed the microSD with Etcher, and plugged it in. Jim A