I did the week-long Code.org training for CSP last year and it was super helpful in terms of familiarizing teachers with their lesson plans. I am positive that after going through that you will feel much more confident and ready to teach the class.
Many of the collaborative lessons are covered and practiced during that training week so it isn't necessary to fully understand or even review them beforehand. However, if I were to recommend one thing that would likely be helpful to go through on your own it would be the programming units (3 and 5). These are the ones that I think that students are most likely to struggle with and it will pay to have some experience with them before the questions come up. Reviewing them before the Code.org training will also give you the opportunity to come in with questions of your own if you need to.
These forums are a great place to come for support as well, either beforehand or during the school year. Also, there is a very active and helpful Facebook group for CSP teachers that I recommend signing up for... https://www.facebook.com/groups/1029824640390220/
You'll do great and you've got plenty of support if you need it so don't worry !