How will my Master-Keys be delivered to me?

Your keys will be delivered to you using the in-game mailing system. You can then pick them up at a mail console which you can usually find near bank access.

What is my in-game handle?

To deliver your Master-Keys to your account we need your in-game handle which you can identify easiest by clicking on your character's portrait in the top-left corner and easiest on a ground map. 

example: @character#1234

How will my EC be delivered to me?

To deliver your EC to you we need you to tell us which item (it can be any item, as worthless as possible) you are going to put up for sale at the Exchange for the price of the EC you want to buy.

e.g. if you purchased 500 million EC you could put up any item for sale at the exchange, we then purchase it and now you are 500 million EC richer and got rid of a worthless item :)