It is actually £5 if you set the account up in GDP, or $10 if you chose that option. You dont have to fill in any codes on the application form, but once you have an account go back to the website and fill in your username on the form and submit it, the bonus money is added within 48hrs.
They are in the TGT reviews at 1* at the moment but thats just the default setting because nobody has been paid yet so we dont know how long it takes and have not had enough experiance of them. They are part of the fortune lounge group though so very reputable, you wont have a problem and it is a no deposit bonus anyway.
The review of the site is here:
Or you can just go straight there: