Zone one is normally assigned to the door contacts. When you open the door, you want to have enough time to get the the keypad (the RKP - remote key pad), so this zone is set as a timed zone, rather than a "go off immediately" zone, and as it went off after 20 seconds, then that's the amount of time set in the system to allow you to get the the keypad and enter your code. Oh, and you enter the user code, not the password - we'll get you trained up by the end of this thread.
If zone 1 is flashing, then there is a fault with the contacts. When you enter your user code, zone 1 will start flashing, but the it should stop after 20 seconds, so can you shut the front door, and set the alarm, and wait 20 seconds to see if it goes out. If you've got a sensor (a PIR) in the room, then stay very still so that you don't set it off.
If you take a photo, when you do your next post, you plug your phone into the computer, click on the paper clip above where you're typing, and then find the photo you want to upload.