The only number I know of is Xfinity support - 1(800) 934-6489.
Comcast -- 1800-266-2278
Once you chose the option for service, look for XH which is usually number 4.
About the test alarm; make sure your alarm is not in test mode by going to your touchscreen, go to settings > Security > Alarm Test. Make sure the button is highlighted Disabled. Then press the home button on the bottom of the touchscreen which is the first button. The alarm should now be off test.
About your water sensor sending a false alarm, make sure your water sensor is not in somewhere moisture can develop around the sensor. For example, if in a basement, have it about 3ft above the floor. Take a look at this page: http://customer.comcast.com/help-and-support/home-control/water-detector-help/
If you want to change the name of Stacy's house. Your rule description may have the name Stacy. Try changing that, or adjust your rules for contacts.