Question: Why did Polly get a panic attack in the middle of the night?
Answer: If you listen to her yelling when they try to subdue her, she yells out "I'm ugly". This is most likely stemming from earlier when Angelina's character makes a comment about Polly never finding love because of the way she looks.
Question: Why was Daisy keeping the old chicken dinners under her bed?
Answer: It is very common for bulemics, as Daisy was, to be embarrassed by the food they eat. It's only natural for her to want to hide her eating habits. She states that when she gets 5, she has to throw them away. You imagine the smell of 5 rotting chicken carcasses under your bed after 5 days. Her father seemed to be a very powerful man so therefore she has some special treatment and is allowed to indulge a little. As long as she's eating, they'll let her have the chicken.
Question: I don't understand Georgina's fondness for the "Wizard of Oz" series. Was it somehow connected to her being a pathological liar?
Answer: I got the impression that she was presented as a "bookworm" (or bibliophile). When Susanna first entered her room, Georgina was reading "The Patchwork of Oz" and had four other books on her bed, plus a notebook with a pen (apparently to take notes for comparison/contrast purposes and/or remember passages). Soon after their introduction, Georgina returned to reading (and ignored her new roommate, for a while). Georgina probably found comfort in reading what might have been her favorite books and reading may have been a way to deal with loneliness, fear, distress, etc. in such an institution. Whether she was obsessed with or fixated on "The Wizard of Oz" series is questionable; having favorite books is not necessarily pathological! But, no, I don't think it was related to pathological lying.
Answer: I think it does play a part. She prefers the fantasy worlds to real life. Look when real life happens, or they hear about something... She looks so distraught and unable to really cope. Telling lies lets her create her own reality that she CAN deal with and be happy in with a sense of control.
Question: At Daisy's apartment, when Lisa asked if there was a bathtub upstairs, why did Daisy lie and say no?
Answer: Daisy didn't particularly like or trust Lisa, plus hesitated to let Lisa enter her apartment. (Lisa apologized at the door for "being a bitch.") When Daisy came downstairs from getting blankets and pillows for Lisa and Susanna to sleep in the living room, Lisa was already snooping around the kitchen (looking in the refrigerator and cupboards) and was "making herself at home" by planning on making pancakes. After Daisy told Lisa where the bathroom was, Lisa didn't even need to use it. Daisy told them that she'd come downstairs in the morning when she was ready. Daisy was basically telling Lisa and Susanna that the upstairs was "off-limits" to them. Lisa and Susanna were uninvited "guests" and already invading her personal space - for them to go upstairs into her bedroom or personal bathroom would pose an even greater threat to her privacy and sense of security. Besides, even family members within the same household don't like getting into a dirty bathtub after someone else used it.
Question: In therapy, Susanna says that her parents are having a "Christmas party crisis." What does she mean?
Answer: She thinks that her parents are mostly concerned about their social image. They don't want people to criticize and avoid them, because their daughter is in a mental institution. They are probably wondering what to tell the guests at their next party.
Answer: Polly freaked out because she had seen Suazanna kissing her boyfriend earlier that day. Polly realised that is something she will never have.