Help! I cant see my channels in the Channel Selection

Hi Cubase Lovers. I am new to cubase 7, but was very good with FL 10. So I know the basics of DAWs. I have recorded my midi. recorded my vocals. they sound good. I need to export all my tracks as separate audio tracks so someone can master them for me…So I want export tracks separately(split) ie i go Export|Audio-Mixdown and on the left I must see Channel Selection and choose Channel Batch Export. My problem is I cant see my channels(tracks) in the channel selection panel. I only see Stereo-Output. Question is: do I need to click on some button on each audio-midi track when I add it initially before it will appear in the channel selection panel for export. I hope I have explained adequately.