Comment 8 for bug 187852

I don't know if this will help or not... it's from the IconFactory about making the icon for disk images. Turns out that the the icns file needs to replace a hidden ".VolumeIcon.icns".

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The following step-by-step instructions will help you out. The “project folder” referred to below is the folder where you are storing the contents of the disk you are creating:

   1. Create the .icns file using IconBuilder Pro.
   2. When you save the file, make sure the Platform is set to “Mac” and the ”.icns File” type is selected.
   3. Save the file using the name “VolumeIcon.icns” (without the period in front) in the project folder.
   4. Open the Terminal application in the Applications > Utilities folder
   5. In the Terminal window, type “cd” followed by a space. Then drag your project folder into the Terminal window. This will save you from having to type the Unix path name. Press return and your Terminal will now be able to work with the contents of the project folder.
   6. To see the contents of the folder, do “ls -la” followed by a return. This should show you a list of the files, including the “VolumeIcon.icns” you saved above and the “Icon?” file created by copy/paste. If you don’t see these files, repeat the previous step to “cd” again.
   7. In Unix the “mv” command is used to rename files. Since our goal is to rename the “VolumeIcon.icns” file to ”.VolumeIcon.icns”, we’ll use this command in the Terminal window: “mv VolumeIcon.icns .VolumeIcon.icns”. Check your typing and press return.

Because the filename contains a period, you won’t see the results of your efforts in the Finder. However, after you burn the contents of the project folder onto a CD-ROM, you should see the icon show up on the desktop for both Mac OS 9 and Mac OS X.
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Good luck