Without even looking at those links, the clue is in the 'up to �3750'.
Which is another way of saying that most people don't win anything like this amount and end up paying for some 'administration cost' before they discover they have actually won less than the price of a stamp.
The profit made on tens of thousands of people from the above, funds the occasional prize, plus a lavish lifestyle for the perpetrators.
Its a con of course, how did you win ? did you enter a competition or did they just pick luckly old you at random ?you will end up paying rather a lot for very little in return, just tell them thanks but no thanks pick on some other poor soul and forget all about it.Dont say we didnt warn you.