Ableton still supports authorizing Live 8 via their website. If you own a license, you can download the installer from your account. However, note that made for Live 10/11/12 will not work.
Live 8’s browser is slow. Stop using the "Places" section for large sample libraries. Instead, drag one folder from your OS directly into Live’s browser, then use the Search field with quotes – e.g., "kick 808" – to avoid a full database rescan. ableton live 8