I've downloaded X2 (and its plugins), and also downloaded & executed the "Additional Content".
Where did/does the Additional Content go?
In earlier Sonar releases, the Help menu used to include links to tutorials and sample projects.
I don't see any such resources in X2.
Help???

Never mind... found them in the relevant folder on my C drive.
(I usually avoid having data on the C drive, preferring to keep it for executable files... but now that I know where the sample projects are, I'm fine.)

Where on drive C did you find the Additional Content file?

Thank's

Sorry... I wasn't clear.
What I was looking for was the Cakewalk sample projects and tutorials. I found them in the folder
C:\Cakewalk Content\SONAR X2 Producer \ Tutorial Projects
 
And those tutorial projects are "referred" to in the online User Manual; the lessons in the Manual refer to specific sample projects.
 
As for the "Additional Content" executable-- on closer look at what resulted when I executed that, I think what it did is to set up a "Welcome Kit" with another tutorial and some more plugins. I probably won't use any of that material, at least not very soon.