Oh hugs, i think the short nAps visited every household, just to test us mums a little bit more!
I know u said that you are slowly extending A time, i think u should continue, the fact that you LO wakes and will lie in the cot quietly sounds to me like she just isnt tired enough to sleep for longer. When i try a d extend a short nap and lo isnt tired enough he screams and screams and screams whilst wen tired he might cry a little but it is muc easier to resettle. Clearly if she slept well before she can transition between sleep cycles so thays not a problem its a matter of finding that perfect A time.
And whilst you are doing that, go with the flow you can only do so much with these naps, if you can go out and she will sleep in the pram for one of the sleeps then by all means do it!