Paymentwall and copy receipt.

Hi.
I'm a new user of both warmane & paymentwall.
When I tried to donate (to get past the queue mostly), I was asked a copy of my ID and a copy of the transaction receipt.
easy enough to upload a copy of my ID. but a copy of the payment receipt... How am I supposed to get this since the transaction can't go on until they have allowed it ? the snake bites his own tail.
I thought : maybe i'll have a transaction appear on my online bank website since I had to confirm the transaction with them, but no, it seems there's no transaction, maybe because paymentwall hasn't allowed it, same problem as above.
maybe warmane will send me an e-mail with the transaction details ? nope.

what do I do ? paymentwall is holding my payment until I provide these informations.
also their widget is always resetting to previous panels while I try to fill the forms...

I just want to play and have fun, first thing I have to pay to enter the serv, second thing it won't let me pay.
not a good first contact with this place to be honest..