Actually, you can fit 16x12 measures in a song (192). They won't look very good but they will play. If you need to fit chords in a certain way you can make them Small ("chords" section, leftmost picker, S), and put N to make them large. As dflat said, even if visually they don't fit, they will play.
If you have 64 one-chord measures, all you need are 8 lines (8 measures per line), and it should still look ok.
The gray dotted line is to show the iPhone screen size - any music written beyond that will make the chart shrink a bit.
If you post the chart here, we can help you understand and make choices.