I thought the card rules said you could use it at an ATM. To withdraw cash, you would use it as a credit card instead of an ATM card with a pin. I've never used a credit card at an ATM, so I don't know the details.
I haven't tried to withdraw cash from an ATM, for I doubt it will work without a PIN. As of using it as a credit card in a shop, I don't know either, but I'll try.
The cards around here are very US centric. Are they blocking you from registering because of your IP address or is it something else?
No, I can see the registration form and I could fill it, but it doesn't fit to enter a foreign address (it only ask me for a US state, for instance), and I don't want to enter fake infos.