We don't know a great deal about Macs. We had to make an installer, and were told to try a .dmg
So we put together version 1, and it seemed to work. We had one application file, which had our icon, and one folder. The user was instructed to drag these into the Applications folder, of which there was the Mac version of a shortcut in the dmg.
Then we were told we needed to update files, and assured that we could do so via drag-and-drop. So we did; we dragged them into the folder in the dmg. We tested it (on the computer we were using to edit the dmg) and it seemed to work. So we burnt it onto a disk (along with a windows installer that actually works!).
I've just gotten an email from the recipient. She's got a Mac laptop. She inserted the disk, doubleclicked on it, doubleclicked on the .dmg, and got a Warning: no mountable file systems. Screenshot:
I have the dmg (not on a disk) and am able to open it with no difficulty.
How can we get it to work for our recipient?