Hi folks!
Since this thread is getting longer and longer, and since mobileread features a wiki which might be better suited to keep an overview about the state of affairs, I took the time and tried to summarize
- the wishlist
- pointers to 3rd party ports
I stumbled across reading this thread.
I hope you'll take it as a condensation point and continue to update them

(the M92 info page was not even linked to the official ebook reader device list before - shame

)
Anyhow, please consider the links added in the 'Related Wiki links section' :
https://wiki.mobileread.com/wiki/Boox_M92
W.r.t. the feature wishlist, I definitely second
- that switching between tools, alongside zooming and panning must be streamlined (going through a menu to the margin-removal zoom to read ; going through the menu to a different zoom mode to scribble on the margins, because panning is not enabled, going through the menu to select panning ; going through the menu to select scribble ; going through the menu to margin-removal zoom to continue reading <- reflects my wished workflow, but contains way to lot menu navigation

... enabling joystick-based panning in the margin-zoom mode and allowing for user-defined long-button-presses/menu - or perhaps a 10-most-frequently-used-items start section in the menu(?) might greatly facilitate things)
- that a 2 column mode (or at least a quarter-page-zoom-mode allowing to flip not directly between pages, but between quarters - e.g., with the joystick) is missing
- that there should be a power management option to power down only after a long period in time (several hours), while suspending the device after a moderate time (tens of minutes). Maybe this could be user configurable?
- that usb host mode support would be a nice-to-fiddle-around (low priority bonus) feature :P (e.g., connecting keyboards might actually come in handy, if someone ever ports a mail application... or connecting 3G sticks for newsletter reading on the road,...

)
I'd like to add that sometimes the choice of different colors in scribbling annotations is a very useful feature (e.g., annotating detected errors in red, ideas in green, and questions/remarks in blue).
This is a feature I liked on my old Iliad device (on the reader, the colors are obviously grayscale, but the merging applications allowed for a color assignment)
Odd enough, I saw in a set of documents I used for testing of my (newly aquired) M92 that annotations in one document were black - in the other: green... can someone explain this behaviour?
Cheers!