Your attached image is about the ACE for the 1011 Captain (FSX/SE/P3D3), not for the 1011 Captain II (P3D4/5). I have attached an image showing the difference between the ACE for both products, and as you will see, there is no PREFLIGHT tab for the 1011 Captain II ACE where you can change the setting between KG and LB.

So is your problem with the ACE for 1011 Captain, or the 1011 Captain II?

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