Re. using the Boot button - if you have to press power and boot buttons together, you only have a short time before pressing the power button for too long just shuts board down. Do you 1. Press and hold Boot, 2. Press and hold Power just until power light comes on then release, 3. Release Boot same time as Power, 5 secs later, after booting from SD finishes - or when?
I tried lots of ways and no good - and read of others not being able to get this to work...