They don't work yet. Either they are sending out paper (like for MU last season when they send some not others and most were left in the dark) or you will have to wait a few days.Anyone else on the print@home league/cups scheme unable to obtain the Dortmund ticket?
The e-mail confirming payment taken did say it would be a mobile ticket - tried it this morning, and no ticket attached.
I have sent an e-mail this morning to City about it, and if I don't get a reply, will try to see the ticket office before Spurs on Saturday if I've got the time to do so.
I think it took a while for the first cup game PaH last season.