I built a watchface on an LG G watch that had 5 or so text elements with a glow and it mostly worked fine on the square G watch. The same watch face on my G Watch R would often cause the TV snow crash. I could still reboot by holding in the button. After rebuilding the face a few times, I figured out it would work fine after removing all the text effects.
Update, I think it may just be adding a glow to the text ring to add a glow to each hour number.