Generally, track info templates work best when in playing now view, or full screen. More often than not, when viewed in the small display window in the lower left corner, the viewable area is too small to be of any real use, so MC defaults to using cover art instead. You can over ride this setting by right clicking in the display area during playback, and clicking on "Show cover art when small" to deactivate it, click on it a second time to reactivate it.
Click on "Playing Now" in the tree.
Make sure audio is playing.
Right click on the display.
Hover over "Track Info"
Click on "Art and lyrics only"
You should now see your track info template in action.
-marko