Hi, I have watched one of the nz bunnings videos on how to lay tile underlay in a shower and in the steps below it has a hint or reminder to not lay the underlay where the shower is going and the toilet. The shower makes sense but not the toilet. I thought you are supposed to tile before installing the toilet for cleaner finish. But if I don't put underlay there then how can I tile there and also it wouldn't be sitting flush with the rest of the floor.