can a 3 dr mg zr bk bumper fit on to my 4 dr rover coz can get hold of a 4 dr

Front and rear Bumpers dont matter for how many doors you have. Neither do side skirts. Every length is the same.

You can put a zr back bumper on your 200.

So get that bumper, you are good to go:)

Not sure about the side skirts because when I was on the look out for some, all the manufacturers made me stipulate whether they were for a 3 door or 5 door on the Mk3 200 as there is a slight difference in length.

I don't actually believe there is, but that's what I was told. I can understand why there would be a difference in the skirts for a 5 door or a 3 door as the fit would be different for some skirts, but not because of the length.