I think Don's problem is the linear rate in the CFG. The linear rate drops if you open PursuitMFD while already docked to another vessel, because it calculates the optimal(?) rate for the total mass of the stack.
Don try this:
While undocked from the station:
Press MOD to go to the "Welcome select mode" screen
Press CFG and then RAT.
Press l 0.5 0.5 0.5 (or whatever rate you want)
(l = lower case L, for (l)inear)
Now BCK, DOC, TGT, iss, LDK, 1, TDK, 1 (or the # dock you want), DIS, 0 0 200 (or any distance you want to line-up) and APD to engage the AP.
If you see the MSG "NO ROLL" or "KILL ROLL" on the right lower corner, press NOR until it goes away.
Once there, press DIS again and set it to 0 0 -1 (this is to avoid getting "stuck" at 0.0001 meters from the dock, which happens sometimes).
Your docking AP should work as intended now.
Still no joy. How long does it take to dock from 30 meters out.