With a screen capture I can only guess but the likely issue here is that you have not zoomed in to enlarge the chord bubbles. Song Surgeon opens with the entire song on the screen. If the detected chords are many, they are all scrunched together and small and the values within them cannot be seen. To reveal or see these values, one has to use the +/- zoom on the lower left side near the chords. As one zooms in the chord bubbles enlarge and when they become sufficiently large to display the text (chord values inside, then you can see the chord.