you can do what it says, you just can't monitor it on the screen in Xara as you work and expect colour fidelity

when I said pointless, I meant from the point of view of colour matching - you will just have to take what you see on the monitor on trust that it will look right when it is printed, which it should if you have used the correct cmyk values and you print cmyk - but the advice is always to check it in acrobat or another proofing program that does have a cmyk colour space [but even then additive colour will never look exactly the same as subtractive colour - the only true test is in the print]