You can use rekordbox ver. 5 on the same computer even after installing ver. 6.

However, you can't run ver. 5 and ver. 6 at the same time.

The following restrictions also apply.

To use selected functions in ver. 5, you'll need the relevant license.

Please note: If you already have a ver. 5 license (purchased or bundled), you can continue to use ver. 5. As of April 2020, it will no longer be possible to purchase a new ver. 5 license key.

To use selected functions in ver. 6, you'll need to take out the relevant subscription plan. When you run rekordbox ver. 6 for the first time and convert your library from the old version, all information such as cues, beatgrid, and playlists will be copied over. After this, the libraries of ver. 5 and ver. 6 do not sync. So, from then on, imported tracks and information such as cue points in one version won't be reflected in the other version.