We have seen a similar issue in the past. The problem occurred when the porcelain tile on the floor did not have 100% contact with the tile adhesive, this caused water to seep down though the grout join and hold in pockets under the tile in the areas where there was no direct contact. The water being trapped in the pockets under the tile does not evaporate and can leave the tiles looking stained. If this is the case with your floor tiles the bottom row of carrara marble tiles are simply acting like a sponge drawing water up. To fix the problem we would suggest that the bottom row of carrara marble and the porcelain tiles on the shower floor need to be removed and relayed ensuring full adhesive coverage. Unfortunately this may compromise your under tile heating and waterproof membrane. Proceed with caution.

It can either look really dramatic or too dark, depending on the size of the room as well as your other components. I've attached a couple of images of our work using dark tiles, the smaller bathroom we have surrounded the bath with dark tiles but then balance it with an extra large mirror to bounce the light around the room. The larger bathroom we have taken the floor colour way onto the wall but used a different texture on the walls for drama. Hopefully this gives you more of an idea but you shouldn't to nervous of the room being dark, it's where you can create a contrast as well as textures. Look forward to seeing what you go with in the end.

Sorry to keep you waiting. Busy as crazy doing another bathroom in the house. Hopefully the last for a while. Yes it is paint behind the vanity. After much deliberation I went ahead and painted it. It is easily wiped down for any accidental splash back but unless your bathing in your washbasin there’s hardly ever any The floor tiles, and in fact all the tiles are from Moorabbin Tiles. Polished porcelain. Thank you for your kind feedback

Hi Di, The glass can be kept clean for longer by wiping down the glass with a window wiper after use as it removes the calcium deposit in the water left on the screen. When it comes to cleaning It is no different to cleaning the tiles simply mist the shower tiles and glass panel with pure, undiluted white vinegar. Let the white vinegar sit on the calcium deposits for 15 minutes clean with a sponge and rinse with water. A glass panel will give the appearance the room is much larger then it is whereas if you enclose the shower area with a tiled wall this will close the room off and can make the shower area closed off and in some cases dark and poorly vented leading it the get mould easier. My Opinion would be to go with a glass panel. Hope this helps with your decision making