Thanks for the advice Tim I am aware that this can be done, but for the few times I have had to do it it is a heck of a lot of work for, in the end, little time saving. O.K. it takes a fair while to get the updating done, but it will take much, much long to study how to slipstream, then I will probably get it wrong a time or two then the updated, tested CD will sit on the shelf of year or so which will then want re-updating the next time I want to use it!
P.P.