I had the glass sandblasted on the outside where it is against the bath. For the step to t the glass I cut a 5mm strip of tile and ground two grooves to match to grout lines, this was then stuck to the tiles with two part resin. As for sealing, I put a very small bead of clear onto the bath edge and the edge of the spacer tile then fitted the screen and put some gentle pressure on the glass to make sure the gap was filled, but the Silicon didn't squash. After that dried I sealed properly using a fugi tool.