DC-3 Aoto Pilot Approach

[Stratocruiser1 134]

I am using the Duckworth mod for the DC-3 and flying the Retro panel. When using the Auto Pilot the NAV and APPROACH functions do not work on mine. Is this normal, or is anyone able to use these functions?

Thanks

[Treetops45 1,082]

I have had NAV work ok, but several attempts at an ILS using  APPR  were not successful as the DC-3 wouldn't hold a 3% descent rate & tended to drop down short of the runway, despite throttle & flap juggling. 

T45