No way (you'd need to enter your e-mail upon registration to make it possible and you don't). Except maybe writing to MarcinS and convincing him that you are you

I don't know the way he stores passwords.
I guess this could be a nice feature to add.
BTW: I learned about png files and I will be doing them from now on, new version of game hall is done, I will send it to you together with deck builder picture which I'm doing right now.