Padlock problems in Great Battles

[buz13buz13]

Padlock works intermittently......on some missions (I fly offline single player)  in settings I have custom difficulty and checked both the padlock box and the Allow spectators.  In quick missions the padlock works on the first enemy aircraft but then none after that....so only the first of three if I have three waves.   If I start a mission by clicking on the map ikon for the country...Germany or Russia and choose the type of mission from the list the padlock never works.  In some cases in a quick mission the padlock will stop working from the cockpit view but will work in the external camera view when the key for enemy aircraft padlock is pressed (not external padlock key)...when going back into the cockpit the padlock stop working.  Padlock works fine in COD Blitz and in ROF and 1l2 1946.  So I can't figure out why it's so intermittent in Great Battles.  Not using Steam...  I would like to know if anyone else has the same problem and if anyone knows exactly what needs to be checked in custom difficulty I would be thankful to be advised.  

[TP_Jacko]

What key binding are you using.

The padlock has a limited  distance I think around 4Km. Beyond that the lock will not respond