1) I chose the easy challenge - I didn't have my book with me to help with the coding descriptions and it has been a while since I worked with it. But, if you look at this project, I did take it beyond what the module wanted. I did this with another person at the first session. We corrected the chemistry, created a water level, and tried to make evaporation happen. We were intending to slow the reaction down with evaporation and lower concentration, but ran out of time.
3) I didn't struggle with this at all.
4) It would be really nice to have a master book of examples of different coding possibilities (what they would do when entered in the correct order - something like a solutions manual)