Amazfit Watch faces

And also i have background problem with this theme, i change it from photoshop keeping same settings but not working. Everything works except background 0000.png image. Also i need help for them too :/

Hey guys,
I downloaded and changing pngs of the gif(already same size) but compiler gives me error
Fatal|System.Collections.Generic.KeyNotFoundException: Verilen anahtar sözlükte yoktu.
konum: System.ThrowHelper.ThrowKeyNotFoundException()
konum: Resources.Image.Writer.WriteImage()
konum ...

how can we edit .json file? Need to be a programmer? I want to design watchface from blank but i dont know how can i do. Anybody can help me about it or do we have any graphic enabled modifying tools?