Run ElkRP on a computer and log in. If you don't have elkrp, you should contact elk, get a username/password and download it. If you don't have an m1xep, then you will need a computer with an rs232 com port to directly plug into elk. You can program this stuff from keypads, but it is a pain in the you know what.
Once logged into your system, using the tree on the left side, drill down to the zone you want to change. Then in the configuration box, use the drop down menu and pick what you want.