I think you err in this respect. They moved outside Scripture to create these heresies (ever virgin and immaculate conception) and in doing so decided that tradition and their power of interpretation (their magisterium) are equals of Scripture. Moving away from Scripture as the rule of the faith has led them to preach a different gospel in which God is dependent upon their cooperation in His plan of salvation.
Now they worship Mary and bow down to idols of her.
It is concomitant with that, but i meant that in and of itself, one can believe in it and be saved, esp. a new convert. But to continue to defend it, in the light of the lack of Scriptural warrant and weight against, does indicate thinking of souls above that which is written in Scripture, which is able to make one wise unto salvation.