The latter is a stripped down version of X-Master for users running low on free memory. It is identical to the full version except for the patch info and the sets functionality. If you are not concerned with the extra KB, install the X-Master.prc file. X-Master is a regular Palm OS application.
Active extensions have a checkmark to the left.
X-Master will recognize if you have HackMaster running and will take over the set of active Hacks from HackMaster. Because it makes no sense to have two utilities with the same functionality, it will then remove HackMaster from your handheld. Note that using multiple extension managers at the same time may lead to unpredictable results. You should eventually delete the other application. You can install newer versions of X-Master over the old version without deinstallation.