I made a dmg of my application with a background image. Because the application runs on older versions of OS X, I tested the dmg on 10.6.4, 10.5.8, and 10.4.11. The background image was only visible on 10.6.4.
As a test to see is I was going something stupid (as is too often the case) I decided to test the disk image for drop dmg 3.0.2 and to my surprise, the drop dmg distribution dmg also only displayed a background image when opening in 10.6.4. No background image was displayed in 10.5.8 and 10.4.11.
Anyone know of a way to display a background image in OS 10.4, 10.5 and 10.6 or at a minimum 10.5 and 10.6?