I'm just getting into reentry with the DG IV. WHen I get into the atmoshpheric regime, 20-30 km altitude, I try to use the atmo autopilot (Prog110SPEC0), but it will not accept changes in heading, and oddly, the craft doesn't go anywhere. It blasts along happily at the heading it wants at about 300m/s, but when I should be approaching a target at 1 km in 3 seconds, I just sit in the same place.
The autopilot works fin after taking off from the ground, though.