It seems the GOG version is not compatible. Any way to make it so?
The GOG version is compatible, but it is a bit tricky to extract the data files. At least I could mount/open the Image of the CD (RTZ.gog) with anything besides DOSBox. So here is what I did to make it run in ScummVM:
1) Open the dosboxRTZ.conf file in the Return to Zork install directory with a text editor. Scroll all the way down to the [autoexec] section. Deactivate all lines after "imgmount d "rtz.inst" -t iso" by writing a # at the start of the line.
2) Right click on the Return to Zork shortcut and select properties. in the target field delete everything after "-conf dosboxRTZ.conf". If you you want to keep the GOG version maybe copy the shortcut to somewhere and edit the copy.
3) Execute the shortcut. You should have a nice DOS prompt now. You need to type in and execute the following commands now (the lines starting with # are my comments what the command does and should not be typed):
# creates out dump directory in the RtZ folder
# switch to the mounted CD image
copy RTZCD.* c:\temp
# DOSBox froze up for me for a few minutes at this command, it seems it is not build for copying
copy *.pmv c:\temp
# those 2 commands copy all the files we need from the CD Image to the dump directory
You can close the DOSBox window by typing exit or by clicking on the close button (if it is not fullscreen)
4) Copy all the files from PATH\TO\RTZ\TEMP to a new folder, whereever you want to put your ScummVM game datafiles.
5) Copy the ripped Music files from the GOG directory (folder Music) to that new directory. You need to rename them so ScummVM recognizes the tracks. ScummVM wants the files to be named track#.ogg. And they start at 1, but GOG numbered them after the track number on the CD. So you need to decrease the number by 1.
So i.e. the first track rtz_02.ogg should be renamed track1.ogg (no leading zeros).
Rename the other tracks in that fashion, like
rtz_03.ogg -> track2.ogg
rtz_04.ogg -> track3.ogg
and so on.
Now you can add your new folder to ScummVM via the main menu screen and all should work. I could not test the music yet I think my renaming should be right, according to the ScummVM docu.
If you can find a way to mount the CD image files (RTZ.inst seems to be a kind of description file for the image for DOSBox) you could save you the whole DOS prompt trouble, but that worked for my quick try.
Please post back if it worked for you or not.