Just letting you folks know that the previously mentioned Green Berets update has finally been released:
http://tain.totalcodex.net/items/show/green-berets-pack
This will allow newer versions of Myth play Green Berets without bugs, and with online coop working.
Don't worry, even the new versions of Myth should still run on os9 computers, so this should just make you able to play it on any system.
hf!