those are intrusion zones, cat just sit there and dont move much when eating or just lounging at the doorway.. when they are still the camera looses them as an object, then they move there head or flip there tail and it triggers a recording.. this camera does not record continuously, just on IVS rules.
linecross dont work well in this situation at all, its gonna have trouble tracking objects that just appear and disappear w/out walking in one side of the image and exiting out the other side.. intrusion on the other hand will go off if an object suddenly appears within that box.