I have the same issue with TouchPad it won't stop asking for login and password. The login part is prefilled with whatever you have registered in SETTINGS/ITUNES whereas the password is blank.
I tried logging in with a newly opened iTunes account, it accepted the log-in but then it popped that it couldn't connect to iTunes Store. Since this a mousepad app it's pretty annoying for users to go through that, however, when I entered the itunes ID login from where it was purchased, the pop ups stopped.
How does the app know if you entered the ID where it was purchased, versus another account? I thought cracking removes all traces of the original Apple ID from the IPA. Or is it just looking for any iTunes account where it was purchased by anyone, not necessarily the original account? What exactly are the developers coding into these apps? Is it something like...
If the App Store receipt is not present then ask for login to confirm purchase.
But then if that is all they are doing, its only doing half to stop piracy. That logic, I think would be followed by
If purchase cannot be confirmed, then exit to springboard.
I guess its good for us here that they don't code that last part, otherwise we would have cracked apps that don't work!