Bathroom tiling

Hi, hoping you guys can help. Installing a low level quadrant shower tray in a bathroom refurb. I assume that the floor tiling goes in after and will need to be cut to a curve to fit around the tray? (probably a stupid question!) Previously run flooring under shower tray but that was using a riser.

Also any thoughts on the sub floor. Existing wooden floor boards are so badly cut and split they need replacing. Chipboard topped with tile backer board? or maybe marine ply?

Any thoughts much appreciated. Cheers.

 

Cheers, appreciated.