Can't open older projects since Logic's most recent update

I recently updated to the newest version of Logic/downloaded the new sound library and now any project that was created on the previous version will not open and I am given a notification that it may be corrupted or in a format that can't be read. I tried opening it on my older mac but that didn't work (logic may have automatically updated) and for some reason the option to open it in Rosetta mode is not available anymore (it does have an intel chip). I tried importing the project into a new one but got the same "wrong format" error. I tried loading previous saves but most of them simply did not show any saves available, which is odd since they had been opened and edited on this mac. I didn't have time machine set up for my older mac so I can't use that to see if previous Logic versions will open it and the other mac is brand new and I haven't set up backups yet. I'm not really sure what to do because the error I get when trying to import the project says I need to open it on an older version and save it but I simply don't have an older version to use.