Yes you would need to perform a find with omit records selected. Your find would be based on the value you are setting in your check box. I assume you are setting the value to "T" or "TRUE"
In your script Specify Find Request
Omit Records table::damaged:[T]
OR IF TRUE table::damaged:[TRUE]
Here's another option:
Print Setup [Restore; No dialog]
Go to Layout ["Inventory List"]
Enter Find Mode  //clear the pause check box
Set Field [INventoryList::Damaged ; "Damaged" ] //specify the value entered into this field when it is marked "damaged"
Set Error Capture [on]
Perform Find 
Perform Script ["Sort by Location"]
Enter Preview Mode [Pause]
Go to Layout [original layout]
Show All Records
Enter Browse Mode