SONAR is a very sophisticated program, it will take you a while to master it. Fortunately you can get the basics going fairly fast. What I'd recommend is just to plunge in, and when you can't figure something out, do a search in the help file...sort of "learning on the installment plan."
Of all the tutorials, I highly recommend the one on compling. Comping is great, but it's not done the way other DAWs (or even previous versions of SONAR) did it so you need to go through the tutorial to have the proverbial light bulb go on over your head.
The major sources of incompatibility with SONAR are third party plug-ins, interface drivers, graphics card drivers (including the "HD Audio" ones that may be automatically installed and are superfluous), and non-updated elements that need updating.
The main copy and paste bug to which I think Stickman is referring is that you can't copy/cut and paste bus envelopes.
Don't ignore the "old" plug-ins. The Sonitus plug-ins are great, and the old synths still make some wonderful sounds. I don't see a synth like Psyne II getting much love, but it's a very flexible and useful synth.