Amazfit Watch faces

Hi, I'm using GTR_Watch_face_(without_Python) for the first time. I've edited one watch face and came up with good results.
but I've noticed something weird. Every time I try to pack the design it doesn't work for some reason. After investigating I noticed that the problem starts once I edit any of the PNG images.

Please help pack my face watch.

all images must be 16rgba exported .