CorelDraw uses this extension, but in your case it should be a S.A.D. mastering series imagefile- it's an adapted Padus .cdi file which is not the same in stucture with .cdi.
You can burn it with CDRwin5, Gamejack, Magix CD/DVD burner and some other "clones" of the S.A.D. software.
All those softwares are... uhm... S.A.D. indeed!
