For those who want to play this great adventure game:
You need to install DOSbox, copy the mastrlu CD content into a masterlu directory on your C: drive, then in dosbox:
mount c c:\masterlu
This emulates a drive like the CD, then you can run install.bat from here, it installs masterlu into a riddle directory into masterlu directory, sets up the sound drivers with auto detect.
After finish, you can play masterlu in dosbox typing masterlu, and if you have flickering or slowmo screen, try to adjust cycles in dosbox
Good luck, and play!