There was no way I could get the entirety of SCUMMVM ported so I targetted Beneath a Steel Sky. It's perfect for children of all ages (though I've cleaned blood from some of the sprites just to be on the safe side) and thanks to the generosity of Revolution Software I could do it without risking any infringements.
I haven't got the whole game in there (yet). It's a constant battle against the 5MB JSON project limitation. There's another 45MB allowed for assets so there's no real problem with the images and sounds (other than ripping them out, converting them and getting them all to play nicely with Scratch). The real issues are fitting all the necessary data into the JSON alongside the script. Oh, and making it performant of course
Anyway, for anyone interested, you can see the current state of the project here - https://scratch.mit.edu/projects/339207237/
It's worth noting that I did have the entire intro sequence that leads up to the initial cutscene working but with over 1000 full screen costumes required it only worked on the most powerful PCs! Not really the ideal goal for a Scratch project.