Region X will allow you to change the region Apple DVD Player is set to, when and only when you play a movie from a region-free DVD drive. You will also be able to modify the left changes count. That is, you will be able to change the region as often as you want.
ECHOROB There is a very simple solution to get around the dvd region code just use FairMount that comes free with the dvdremaster package. Set it to always open when a dvd is inserted in your preferences under cd's/dvd's (Version 1.2)
XYPHER Here's a solution for using the app with a region free drive under Leopard. (Taken from a forum).
"Delete the ~/Library/Application Support/DVD Player directory and the ~/Library/Preferences/com.apple.DVDPlayer.plist file. After running Region X again, and modifying the zones, DVD Player will now be aware of the new settings." (Version 1.1.3)