Sonar always uses the first one created (T1), so I can create/put MIDI clips on/to the T2 one only with drag and dropping from the T1 (or other places)  :S 

(offtopic but Cakewalk should promote StreamworksAudio youtube channel better, I've just found it luckily, the 50 parts Sonar series is quite nice www.youtube.com/playlist?list=PLKRYWdEpbc5PgUgvrNuSvVyfv5qkll0qj  + the new ones about X3 www.youtube.com/playlist?list=PLKRYWdEpbc5MtPslyvpY_tkunB34cvU75 )

Every time I have tried to access those via SWA's site they never came up. That set of videos has a lot of nice info in them.