The Xephyr server is recommended since it tracks the newest X server extensions used by Fremantle.
Find this in the Xquartz project.
The Xephyr server uses the desktop's display depth and Fremantle requires a 16-bit display. If possible, set up your display to have "Thousands" of colors in the System Preferences > Display field.
If you run under a 24-bit display, the Maemo AF will not show up properly in the server (applications will be invisible or corrupted).
If ESbox notices that you are trying to run X in an incorrect configuration, it will ask you to disable the MIT-SHM option, which is a workaround that fixes the issue:
Click 'yes' to warning above to disable MIT-SHM extension in the command launch pattern in the ESbox > X Server preference page and restart the server.