Hi Marc,
My Edge upgraded just fine this time, no space issues, five minutes and done. Great work.
On the Lite it is a different story however. I did like that it can remove the DataMine files for a better chance and it gives a proper warning before starting, but still failed even when sufficient space in /overlay was made free. I removed more files and maybe one too many as it bricked the Lite. I just did a firmware flash and now it is upgrading again, keeping my fingers crossed on how it will look once done and I have restored the backup.
I was monitoring the commands executed and I do find one thing realy strange and it seem the bottle neck in the space issues. The new firmware is first loaded to the /tmp folder. Then the script copies that to the /etc/cmh-firmware folder (6MB or so), and then the install script seem to use the file in the /tmp folder !?!?

/bin/ash /sbin/mtd write /tmp/newmios.squashfs mios
/usr/sbin/nandwrite -p /dev/mtd8 /tmp/newmios.squashfs
So if you guys can eliminate the (redundant?) coping to the /etc/chm-firmware folder upgrades should just work again, as on the Lite it has become seriously troublesome.
But, keep up the good work.
Cheers Rene