It goes back to the old schedule when I restart ChurchBells.
(Either the license did not take, or you have the Home License.  If you have the Home License and you want to be able to create custom schedules for yourself please purchase the upgrade from the link above.  If you tried to license the Organization license, please click on Registration in ChurchBells to verify your license level.)  If the organization level license is already installed, please make sure that you are really saving your schedule.  You can now find a pretty good primer on how to create custom schedules from here:

http://inspiredcode.com/contact/cbc1.htm