The Church Conservation Trust is:
“the national charity protecting churches at risk. We care for the churches vested in us by the Church Commissioners of the Church of England, repairing the damage from sometimes years of neglect, and work with local communities to bring them alive again”
A few of the churches are in Sussex and this example is within walking distance for me in Hove. The web site advises to obtain a key from the Iron Duke Pub opposite and I was able to let myself in and wander around. If you go up the stairs just as you enter you can gain access to the gallery.
Returning to floor level towards the altar, looking up you can see another decorated sky light and the wonderful circular astronomical ceiling.
The light was a little against me for a picture of the font and side chapel window.