I finally managed to upgrade my Mac OS so that I could upgrade Premiere to CS5.5. BUT my project files from CC 2015 will not open.
Premiere states the “Project is damaged. Opening impossible.” Apparently this is typical.
I have tried not only to open, but also to import. No success.
I have tried opening and re-saving on a windows machine, no sign of damage. But the newly saved version will not open in CS5.5.
Finally I managed to start up an old copy of CC2015 again. The project I was trying to open is fine, not damaged.
How do I open an old project successfully in CS5.5?