The link to the download page is on the program if you have the Windows version installed. You should have also bookmarked the download page previously as noted in the instructions. If you need help email me and I will answer as soon as possible.
If you are using the Windows version it is best if you uninstall your current version first but it will work if you don't. If after you do the install it does not say version 4 at the bottom of the PDF then uninstall and reinstall with the current download.
If you would like to order the PDF catalog the click this link. There is a video on the page explaining what this catalog is. It does not replace the free online catalog. This is just a supplement to that catalog.