Hello,
Thanks for reaching out! You can move the button to the left side as one option by using the position parameter in the right rail:

If you want to keep the Buttonizer button on the right side, you can also adjust the z-index for the Buttonizer buttons by adding this custom css to your site:
.buttonizer {
z-index: 99 !important
}
You can increase/decrease the z-index value until it is in a good place (behind the shelf element that flies out). Hope that helps!