Upgrading PE7 to PE15 on my Windows 10 Desktop PC

I have PE 7 installed on my Windows 10 PC with over 8000 photos nicely tagged. I have just bought a new CD copy of PE15 and want to install this on my Desktop. I have read about compatability problems with regard to Catalogues and thumbnails and I am concerned in case if I just load the new CD to install my PE15 I might lose some of my existing Catalogue/Thumbnails/Tags. Can you advise me the best procedure to as it were upgrade my existing PE7  to PE15?