As per this thread - same issue.
Hello,
I have a similar predicament, although I am utilizing the Creo Parametric 6.0 tutorial book by Roger Toogood, and the exercise files were saved in the Commercial Format. I am currently trying to learn Creo for work, and before purchasing a license for me they would like to see that I have some basics down. Are you able to convert the files to a student license version, which I am currently using? here is the link to the website where they are downloaded.
https://www.sdcpublications.com/Textbooks/Creo-Parametric-6-0-Tutorial/ISBN/978-1-63057-291-4/
Thankyou for your help,
Gabriel