Running old games without CD I want to run Diablo (Windows/Mac game) on OS 9 but without using the CD. After installation, the user is required to insert the disc for the game to start. Making a .dmg image didn't work (as suggested by a website), as OS 9 doesn't recognise the format. Anyone knows something that might work?
Try creating a .img or .smi file. 

To get from a dmg to an img try the following:

hdiutil convert /path/to/file.dmg -format RdWr -o /destination/of/file.img