I think I have a SOLUTION for at least some of these issues. I have a Cambio W1162 Windows 10 purchased December 2016.
Symptom: From full power off, the power button only works about 1 out of 10 tries. (I hold it down for 5 or more seconds)
FIX: Un-check "turn on fast startup". After doing this, it powers up every time.
THEORY: I suspect that choosing "fast startup" is the same thing as "Hibernate". I further suspect that there is a timing race condition in the firmware of the tablet or in Windows 10 startup software routine.
DETAIL: There are a number of confusing routes to accomplish this, so experiment. I use the "settings gear"... > power options > Choose what power button does > "Change settings that are currently unavailable" > UN-check "Turn on fast startup" > "Save Changes"
FYI Google "Confessions of an Old Geek". Enjoy