We were there on Monday and the park was busy. They seemed to open gates around 8:30 the time I was in bag check, we waited in the line a bit to enter, and I walked fast to the left side of the park. Rope was still up to go toward TSM. I was not 100% certain where to go for the line so I walked a little bit, totally confused by the Indiana Jones set up. A nice dad directed me, and I headed in line, only then to discover the kids had to be with me. My text to my husband telling him to bring me the kids was sent at 8:52. They started to count the number of kids in line before my kids were there and I told them I had 2 kids....not a problem. My kids joined me in line before 9. By the time I got to the counter, the first show I could for my two kids was about 2:30. (Single child sign ups were available for about 12:30 or so. We picked the 3:10 show and had to be back by 2:40. Having said that, they had lots more availability to sign kids up after us. The line was pretty efficient and went quickly.
I have to say, this experience was worth it...for my 5 year old son who LOVED it, for my daughter (7) who admittingly was luke warm on the idea, and for us as parents. I admit I'm not into Star Wars, my husband has seen them but certainly isn't a huge fan but we thought it was awesome! My daughter knows that characters are dressed up people but she was intimidated by the thought of fighting Darth Vader. She wanted Seventh Sister. Both my kids got Darth. Based on something I read here, I thought it was based on height. It is not. My kids are both short. It's what side you sit on during check in, and to some extent how early you check in. They do line the kids up based on height, to get fitted with robes and to do the walk to the stage, but they are kept in the lines they chose.