2 min job to remove water mark.
There is things out there that giggle with the wording and letter spacing to let you know where things are from but i would have thought there are to many copys to do it with.
As this issue has been active all the time i have been in aviation, I suspect its just an outright refusal by the caa to admit its not fit for use. And there arn't huge numbers of ppl's falling out of the skys. So apart from the sheer bad taste that cheating gives it doesn't seem to be having an effect on flight safety.
Back in 2k you could get a copy of the papers in the barras for 3 quid and the previous time i had seen them they came with a hooky copy of ms simulator in the early 90's, so its hardly a new problem.