I had a small puddling problem with my 18SB when I couldn't get it perfectly level due to our spot.
Basically the water would run down the shower wall, then along the wall and pan and out onto the floor. From there it would travel wherever gravity would take it. I honestly thought at first the inlet on the back of the toilet was leaking.
Once I figured out what was happening, I used some tub/tile caulking to create small dams on the bottom between the wall and basin that would deflect any runoff back into the shower.
I have not had any issues since as long as the person is very careful to make sure the curtain is tightly closed all the way around. Any puddles now are the result of a shower curtain not closed all the way.