Can the newer version of the product be able to work with files that were created in older versions? I have many files created with version 20 and I'm thinking of upgrading the program. Will I be able to work with these files?
Yes. According to the following official support page, files that were created using the 20 version of the program can be used on newer versions. To use them, you need to use the Import option that you can find under File > Open > Open existing file.