Dawn,
Since I got into the 9600s late (you were the one that introduced me to them) I never used PEP 1. I had used pronto edit for the 7500 and did not find it difficult to transition. The biggest learning curve for me was prontoscript. I have been doing programming for a long time and just had to learn javascript/prontoscript. I think installing it and just seeing if you can download to the 9600 under windows 10 might be your motivation to move to PEP 2. Someone else may be able to give you a better PEP 1 to PEP 2 transition experience.