Simon on this forum, along with myself have managed to get the 5" 800 x 480 Capactitive Touch displays from Newhaven to work with the G400 and G120. Simon did some excellent work on the touch driver and I manage to get this working with Clix2 and also Glide.
These are beautiful displays with nice high brightness although not up to the resolution you are looking for.
It’s not a drop in for Gadgeteer as such although I do now have a design for that but it hasn’t been made into a real board yet and tested but I know the LCD interface works as I used the same basic layout with a G120. I have another connected to my G400 board which also works.
If there was enough interest for it, I would get it made up and tested and then offer them through Creations.
I don’t really have a minimum resolution (800*600 seemed about right, as I’m used to old-style CRT displays :-[). Right now I’m just evaluating my options, so I’ll take a look at these.
I’ll have to take a look at the ChipworkX devboard schematics to see if it can replace the existing display with minimum (maybe even none) modifications.