I accidentally deleted Ableton Live 8 Beta from my computer and can't get it restored. Will this version be compatible with all my Ableton Live 8 Beta files? If not, which version can I buy with add-ons that will allow me to use my same files?
It's uncertain to say if this version will work with your files, but the files coming from a precedent version should be compatible with a newer software version. However, you can't download version 8 because it's not available anymore.
Nowadays, a new version has been released for users to test in the trial format. Use the following link to obtain an installation package: https://www.ableton.com/en/trial/