is your scripture different than sunni Islam? Do you have another version of the Quran?
If you are, then okay.. its another religion. If you are not, then you are probably following different interpretations. I have no idea how you can go around Quranic interpretations that are supported by Hadiths from the prophet himself.
Also, if you believe in the Quran + another new book then again, Quranic mistakes will haunt you.
I don't know which system you follow.
I have no knowledge of how Ahmadia work... they are considered infidels by sunni muslims because you believe in a new prophet after mohammed