can't open 5.4 file in 5.6 or 5.8
I have an ardour 5.4 project which I can't open in 5.6 or 5.8. I recently went from Ubuntu 14.04 to ubuntu studio 17.04, so I don't have ardour 5.4 anymore on the old OS. I can start a new Ardour file in 5.8. There is now a desktop configuration file which also won't work: Failed to execute child process “/usr/bin/ardour5” (No such file or directory). Any suggestions?
Is it possible to install 5.4 on the new system till I figure this out?