Hooo thanks a lot for your quick answer !
I have already read this paper about submission. I think I respected the submission rules ( the 2 images, image quality, no copyrighted material ).
Did you see the pictures in my post ? They are taken from the GWD app so I suppose the size and quality are adequate.
So maybe it’s my design that is bad ?
What do you think ?
Frankly any critic or suggestion will be welcome, I would be happy to share my watchfaces 
Thanks
Laurent