You may want to check to see if your Anti-virus software is having an impact.
I have a pretty fast machine, but experienced similar problems. The solution for me was to go into the settings on my anti-virus software (in this case, Kaspersky) and set up the 'exclusions' option. This allows you to prevent the AV software from scanning specific files/folders each time Cakewalk or Platinum starts or opens a project. I think most AV software provides this exclusion feature. As well as your main Cakewalk program and project folders, you may need to exclude non-obvious folders such as c:\ProgramData\Cakewalk etc.
In my case setting Cakewalk folders to be excluded from the AV made a dramatic difference to load times.
I hope this helps.
Tom