As far as I know there's no such document required in AP EAMCET councelling many students drop a year or 2 after 12th for preparation for entrance exams so need not to worry about that. Moreover you should be required the actual application form as it is the very basic and important document the xerox might not be allowed. If you have lost the registration form try to download it again and if you failed to do so then I would suggest to write an email to them and ask whether you could bring a xerox with your or not and if not then what else can be done about this.

Hope it helps.

Thank you.