Thanks for that, I don't know of legalities regarding this but would guess it's a definite no- no . I asked the studio I intend to use and they basically said so . ,that's their integrity intact lol so well done them !!
I have looked into the make your own karaoke thing but seems the results are very poor and unsatisfactory.
One glimmer of hope I have found is a custom made backing track as near as possible to the original at a cost of 50 euro. Some very good feedback and reviews. Always assuming these are genuine ! Always gonna be a gamble I suppose but not too much to lose I guess.
Thanks for replying