Your concrete specialist will have ways of sealing/coating the concrete in a low-slip/textured finish. This can be done by texturing the concrete while wet and by using a textured epoxy with low-slip properties. Ask your concrete specialist what they recommend when used in a wet environment such as a shower.

we put ours in the middle of the slower floor with everything sloping toward it. well, no, i mean we put it in the side to side middle, its about 1/3 of the way end to end, under a rainhead.

Yes the windows are in place and I’m sorry I didn’t see this before we had to make some decisions

I am trying to source (in New Zealand) a shower tray which will fit into my alcove Sized 1900x1000 for the shower. Thus far for that size (and I have searched online and in merchants) found only tiled over solution to completely cover floor space. Not totally happy to have this as feel that tiles will be slippery when wet. Whereas have found smaller acrylic trays that are described as non slip even tho they are smooth. Can anyone suggest a supplier that they have used for trays and hinged/pivot doors of the size I require? Or if place a shorter acrylic tray to the length (probably 1200mm) of the glass wall, as will create a walkin with what do I cover the remaining 700mm of the alcove floor? The bathroom floor will not be any kind of tile, more likely to be a textured vinyl plank.