Upgrading from 1.10 to 1.2.1
I followed the video, since I had to remove the micro SD Card.
A couple of points.
a) Upgrading onto the MicroSD wipes out all of my saved files (fortunately they are all on my computer) - I should have known / thought about this - but didn’t
b) In order to get to the Micro SD, the I needed to remove the internal ground wire temporarily, since it was short and prevented the front cover sliding out far enough to be able to remove and replace the microSD.
Other than that, it went pretty well. Nice job.