Anywhere in the active range will be an efficient burn for your Kuma LE-1 series wood stove or insert. When the indicator is straight up (at the 12 O'clock position) the catalyst is at 900°F: Anywhere between 600° and 1300° is an efficient burn.
The maximum allowed operating temperature for the catalyst is 1600°F so, as you can see above, you will not damage your catalyst if temperatures occasionally go beyond the active range.
The maximum recommended operating temperature for the catalyst is 1300°F, so as you can see above, if the temperature of the catalyst goes higher than the active range you are exceeding the recommended operating temperature.
The recommended minimum light-off temperature for the catalyst is 500°F. On a cold start-up this probe will have a slight delay so you should engage the bypass when the indicator 1st reaches the hatch marks.