how to. set magnetic variation manually

The manual states on p38 "Magnetic variation is defined in the last tab of boat’s settings:"
but when I go to settings and click the 'boat' tab, I do not see the image presented in the manual
(which I have copied and attached below)
Where is it?

you need to go to the 'boat' menu then 'boat settings' (not Qtvlm then configuration then boat)  
 

thank you. the manual shows 'magnetic mode' radio button highlighted. what is the 'true mode' button for?