For windows you want secured at night (such as downstairs windows which are easier to access by criminals) use these settings:
Device type: Window Alarm
Zone Attribute: Stay Arm Active
For windows you may want to have open in the middle of the night such as upstairs bedroom windows (where its safer to keep open due to being harder to access by criminals) use these settings:
Device type: Window Alarm
Zone Attribute: Out Arm Active
OSI Mini-Alarm: Recommended settings to use for contact sensors used on windows - Click here