Don't have this keyboard, but if it's connected via USB you should be able to find the driver here:
http://www.rolandus.com/p...ails.php?ProductId=864 Click the downloads tab and select the version for your operating system.
There's no drivers specific for any particular DAW, just select the one that matches your operating system.
After installing, open Sonar, press P to open the preferences dialog, select the MIDI\Devices section and make sure under the Input list there's a checkmark in front of your device name.
You may need to restart Sonar after doing this.