Oxymoron, so sorry this screaming is so bad. Try and keep in mind the fact that you know your baby is going to have to learn to go to sleep on her own some time, and at least doing it now will work more quickly than when she's older. I know it doesn't feel like it now, but trust me. We left DS (or rather, tried so many different approaches that he didn't know what the rules were), and it was a lot worse having a 2 yr old crying at the top of the stairs "Mummy, mummy, please can you come and see me" than listenening to his baby cries.
We've "fixed" DD (7 months) much more quickly, although if she'd been my first child I would have had trouble listening to her cries too. it was only the advantage of hindsight from DS that helped me stay strong this time.
Monekysmamma, my DD does this:
7am get up.
9am nap
9.30am get up
12.30pmnap
2-2.30 get up.
6.30-6.45pm bed
If she isn't already awake by 7am, I wake her up, so that her daytime sleeps can fit round our other activites. Once or twice i've let her sleep in till 9am and then she only has one nap a day and it's awful by bedtime.
Sometimes I tinker with the nap times as 3 days a week i take DS to nursery in the afternoon and am not back till 1pm so have to keep DD awake til then. To do this I push the first nap back half an hour.
Like yours, she used to only catnap (2 x 40 mins sleeps if I was lucky), and it was hard to get through the afternoon. We sort of settled inot the current nap pattern with me keeping all her naps at home in her cot (I found buggy and car sleeps neve lasted long enough), and leaving her to cry if she wakes from the munch nap after less than an hour. Sometimes she chuntered away for 20 mins or more, but it was just grumbling and she then went back off for another hour.
We adopted the same approach at night and now that she has this nap pattern, plus a full night's sleep, she does really seem a much happier baby, much less grumbly in the afternoons.
Damn, I've probably jinxed it now!