I think we need to hear about your routine before we recommend nap capping. Can you post the average day? Not the ideal, more as it generally works out.
If I had been outside the door trying to calm with my voice, and then needed to go in because that wasn't working, I would go in, if there is no need requiring attention, sit down beside the cot (or elsewhere if normal) and say 'time to go to sleep' (or your own phrase) and just be very very calm, while LO settles down. Or, you can go in, check everything is ok, not sit down, and say good night or whatever, and leave again, and again attempt to reassure from outside the door. When my 2 yr 10 mo kicks up a bit, often the second go goes very smoothly if carried out exactly as a 'usual' bedtime would be, without any reference to her calling out etc. At this age, I would not lie her down, I would expect her to lie herself down, perhaps with some encouragement like patting the mattress or saying 'lie down please'. Physically lying her down will cause more stimulation/excitement if she resists.
