I was using PSE 9 on windows 10, just got a mac, installed PSE 2020. Backed up catalog on mac and tried to import to mac PSE 2020 and it imported folders but nothing in them. I am afraid that since pse 9 is 32 bit and pse 2020 mac is 64bit, the catalogs will not import correctly. I don't want to have to reload 6000+ pictures and recatagorize them, oh me. Any help?
You need to use the Organizer backup & restore process. Start with full backup of PSE9 on the Windows machine. You will need to use an external drive formatted for both Windows and Mac e.g. Fat32. You can then restore into PSE 2020 Organizer on the Mac by connecting the compatible drive to copy the catalog database and all the image files.