There are two solutions that have worked for me and others - one easy, the other more drastic. The easy one is to add R-Pro (and Sonar and Cakewalk content folders) to your antivirus exclusion list, and the drastic one is to uninstall Rapture and Dimension pro, if you have them, and then uninstall/reinstall Rapture Pro *first* before reinstalling Rapture and/or DimPro, if you need them for existing projects. Between those two I got my originally *very* long load time down to a quite reasonable 10-20 seconds or so. And I'm on an old, slow machine...
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