he code below will enable you to hide (disable) the Register button in your app:
1) Log into your App Manager and select your app.
2) Click Colors from the left-hand-side of the screen (or the middle of the screen).
3) Scroll down to the Advanced SCSS box. If there is already code in the box do not delete it! Simply add this code “below” the last character of code in the box.
/** Begin hide register link*/
.item.item-icon-left.item-custom.ng-binding:nth-child(5) {
display: none;
}
/** End hide register link*/
4) Click Save.