I had to rebuild my server from 'scratch' recently. Provided the licence is still current, CWP Pro will automatically re-install when the automatic update script runs (I'm not sure how frequent this is, but I don't think it's daily).
If you don't want to wait you can always open a PuTTY or Terminal session and call:
/bin/bash /scripts/update_cwp
That should update to CWPPro straight away.