Flash 4 and Macintosh Executables
Since version 4, Flash allows the developer to create on the PC both a Windows program and a Macintosh executable.
The Macintosh files created by the program are BinHexed Files.
They need to be correctly managed to avoid losing their executable property. See our page on Macintosh File Forks for more information. Particularly, don't try to unpack this container.

Solution With MacDisk
You simply open a Macintosh medium and copy the file to the Macintosh volume.
MacDisk detects that the file copied is binhexed and decodes it on the fly to manage both forks and put things where they belong.
Put the disk in a Macintosh and you'll see a Macintosh application waiting for you, just a click away...

Solution With MacImage (Hybrid CD-ROM)
In the Project mode (default mode), just drag-and-drop the original file to MacImage window, in HFS view (the ISO view can't do anything with this file, which should not be shared).
MacImage detects the binhexed file and extracts the necessary information.
On the other hand, the swf files are dragged-and-dropped to the hybrid view, to share them between both views (between both executables).
When you compile the project to produce the CD-ROM image, the BinHex container is broken and both forks correctly copied.
After that, you burn the resulting image with your favorite CD-ROM authoring tool, telling it that this is an ISO image. See our CD-ROM FAQ for some comments on the different software packages.

Second Solution With MacImage (Mac-only CD-ROM)
In the second case (HFS only CD-ROM), switch to Partition Mode and create a new partition. Then copy the MacBinary file to the Macintosh virtual medium, as explained above about MacDisk.

A Web Site on CD-ROM
Glenn Corbet, user of our MacImage, took the time to write down a tutorial with screen shots to illustrate a similar method, but using some Flash programming. Please visit his Tutorial.

A FAQ on Cross-Platforming With Flash Projectors
I've found another very interesting page on cross-platforming with Flash projectors, collected by Radina Matic from the messages exchanged on the www.actionscripts.org forum.

Flash and Subfolders
The Flash documentation explicitly says that the data files (*.swf) should not be put in a folder tree, that is that they must be in the same folder as the projector. It seems that this restriction is not quite rigourous on the PC, but that it is applied strictly on the Mac. We have been told of presentations working with several swf files scattered on a folder tree on the PC and only showing the root files on the Mac.
Beware!

Flash and Levels
Note: the lines below are the result of the observations of Thierry Peterburger, who spent a lot of time to ascertain the facts and even draw the pictures. Thanks a lot, Thierry!
There are no special problems when coding simple Flash projectors containing a single level. However, if your Flash contains several levels, some special measures are necessary:
On the PC side, the application can contain a level whose role is to start the other ones (see picture below). On the Macintosh side, the application starts but doesn't display anything (black screen). You have to ask the projector to start a special file (constructor) which will load the level constructors (see below).

Flash 4 and Autorun Under Mac OS X
Curiously, Flash 4 executables run fine under Mac OS X but can't work as the autorun support. Nothing happens when the CD-ROM is loaded in the drive, but the executable runs normally when directly double-clicked. This doesn't happen with Flash MX (aka 6). I don't know exactly about Flash 5.