Attachment Therapy/ Nap Hurdles in School?

Has anyone had experience with daycare, pre-school, or schools following a different form of discipline that sometimes seems to counteract what you have been practicing in therapy with your foster kiddos? Some background... Our 3yo foster daughter has been with us for 15 months, along with her 4yo brother. Our TPR trial is early next year, and my husband and I have been named as adoptive resources. When FD first came, she was very withdrawn and sullen and didn't react well to physical touch or attention. She was the youngest of six in a blended family, born less than a year after #5, and we've theorized that by the time she came along, things at home were so bad that she didn't get much early bonding. Four teeth had rotted out by the time she came to us at 2.5yo and her leg muscles were stiff as boards. Mom admitted that FD spent a lot of time in a carrier with a bottle propped up in her mouth. Her coping mechanism to deal with human interaction was to turn her head and say "Don't talk to me." We asked for therapy from the beginning, but the caseworker declined our request, stating that he didn't think play therapy at a young age would make a difference. We asked for additional appropriate training for dealing with possible attachment issues, but it took a new coordinator coming on board to recommend us for therapy. In that time, she made a lot of progress, but also suffered a lot of emotional setbacks with her bio Dad stopping treatment and visitation, and her bio Mom missing over 50% of her visits, including around holidays and her birthday. We finally started therapy in the Spring, and by the end of summer, her therapist recommended someone specializing in attachment. Her behavior is unpredictable. She can go from sweet as pie to full out raging tantrum in seconds, complete with physical violence, spitting, screaming, and attempting to destroy her surroundings. In therapy, we have been working on attachment and bonding. Although she expresses her love through words and affection, during her rages she becomes angry and refuses our calming words, sometimes screaming that we don't love her. We are totally committed to working on attachment and helping her come to a place where she feels safe and loved. Sometimes problem solving as suggested by the therapist seems counter-intuitive. Giving her some control and focusing on the bigger picture of attachment before expecting obedience seems to be the key to the progress she's made and we can see her becoming more content every day. Truly, we have tried nearly everything else. Our therapist feels that she'll continue to struggle until she has consistency in her life, and that makes total sense. Our problem now seems to center around transitions, with a big emphasis on sleep. She is, and always has been, terrified to sleep. She has occassional night terrors, screaming and crying in her sleep. We have no way of knowing if she witnessed or experienced something terrible that she associates with sleep, if she is afraid to let down her guard, etc. At home, we can stroke her hair and stay with her until she feels safe. However, she refuses to sleep at school. She is in a pre-school class that has a mandatory nap time for around two hours. If she does not sleep, she is expected to quietly look at a book or lay in her cot. If she cannot remain quiet, she is punished in the form of taking away outside play, which she loves. Her therapist was appalled when I told her about the situation. She feels that given the circumstances, FD should be given a chance to nap for 20-30 minutes. If she cannot fall asleep, she should have the option of going to another room. The therapist feels that it's unreasonable to expect her to sit quietly for hours when she is unable or unwilling to sleep, and that punishment for not sleeping is counteractive to the attachment therapy were working on. Since her teachers have begun instituting the "not quiet at nap = no outside" policy, her nap time behavior has gotten worse. It's almost as if she now associates nap time with something she's failing at and is shamed by, when everything that we've been working on in therapy points to negative behavior associated with sleep being a coping mechanism. I asked her teachers about another option, but there isn't one available. She doesn't have to sleep, but she does have to stay in the room and be quiet. Every night before bed we talk about the day we want to have tomorrow, and she always acknowledges that she needs to be quiet at nap. Every morning when we drop her off, we reiterate the need to be quiet. And yet, every day I come to pick her up only to find her sitting alone with a teacher because she's been disruptive (talking, singing) at nap. Today she was not allowed to take part in a cupcake party for a classmate's birthday. That breaks my heart. I am so torn on what to do. For starters, I'm a teacher myself. I completely understand classroom management and the need for natural consequences. I also understand the need for her teachers to protect the other students from disruptive behavior. And, I get that if the class sees our FD being able to do something other than nap, then they'll want to do the same. Her pre-school is amazing. Everyone is understanding of her situation and accommodating for visitations. We drive out of the way to take the kids there because they're known as an outstanding school, and we waited 3 months to get them in. This has been my only semi-issue in a year of them going there. Has anyone had a similar experience? We are admittedly new at dealing with attachment. Is this a case of me assuming that school behavior is a result of some internal struggle she has inside, when it's actually a simple discipline problem that should be dealt with accordingly? I don't want to make excuses for FD's behavior. At the same time, I want to make sure that the deeper issues surrounding some of these problems is being properly addressed. Any insight or suggestions are welcome!