Uncheck the box "Optimize Mac Storage" if you have enough space on your drive.
According to Apple’s instruction manual I understood that files would be stored on the cloud only if the Mac were running low on space. My 14” MB Pro has ample storage space left, and so I assumed that all the original files would be stored on the internal solid state drive. Much to my surprise, the large Master file that I needed for the template was not stored on my Mac.