This is a continuation of the thread Build red_WP76xx fails, and a repost of a thread on the Sierra Wireless forum (WP7601 update fails - no redSensorToCloud).
In brief, the startup documentation says that after building (in my case red_wp76xx) and updating the MangOH-Red with the resulting file, you can check if the update was successful:
If redSensorToCloud is listed, the install worked.
But it says nothing about what to do if redSensorToCloud is not listed, which was the case for me.
I can upload the output of “logread -f,” which contains a number of error messages, or you can follow the 2nd link above to read my post on the Sierra Wireless forum.