I've continued to take some photos as I develop this painting. Excuse colour variations. There was no one around to take some of the photos for me and it's hard to take a photo with your left hand while you paint with your right.
Once I removed the masking fluid which was protecting the rose and leaves while I painted the background I then used a pencil to draw in lines to help me see where the light and dark shapes were on the broken leaf. Painting glass is really just painting shapes and my pencil lines just help me to see where those shapes are.
Then I painted in the darkest areas first and gradually built up the leaf with a succession of glazes.
with the broken leaf completed I can now turn my attention to the glass rose. I am really pleased with the high key effect that is developing.