Only thing it allowed me to add it to my cart was Dawn of Magic... and once I downloaded it, it seems to have no language options of course. lol
edit: And it took my email the first time, no problem. I didn't use a proxy either (though everything but Dawn of Magic states you need to be in Poland, so you would need one then). Maybe try signing up without a proxy like I did, then go back for whichever other titles you wanted.