When using Scummvm to play Myst Masterpiece Edition you need a list of files and a QTW folder.
The bug: in normal mode is that you cannot copy/paste the QTW folder because it is a read only folder.
What I did is to go in "Safe Mode" / copied & paste that folder on the safe mode desktop and it worked.
Back in normal mode I was able to copy & paste that QTW folder in my Files for Myst folder on the desktop.
The list for M.M.Edition can be found here under the Myst Masterpiece Edition Windows section...