If you have the hunt type set to linear, then provided all extensions are logged into the group, the call will bounce between the extensions in the order that they were intially added to the group. If you want to set an order, then remove all the extensions. Then add the extensions back in in the order you want them to ring. I would recommend that you have all the extensions log out of the group before doing this. You may also want to do this after hours and possibly reboot the system after the changes. I have found that groups don't seem to always act how you configure them until you reboot the system.