@ozkano
Can you do a soft reset and get to the early startup menu. If you can try booting without startup sequence and see if you can get a shell window.
If you do get as far a shell window try typing the following;
unlock_eject macminiide.device 1 (assuming that unit 1 is the CD-ROM)
I think to stand any chance if booting into workbench you are going to have to make a new ISO with the Moana files and the files from the version of OS4 classic that you bought.
