Gravity Perks - eCommerce Fields 1.2.30

Fixed issue where product-specific discounts were incorrectly calculated when the product total was 0.
Fixed issue where {subtotal} merge tag replacement was inaccurate when multiple Calculation Product fields contained a {subtotal} merge tag.

Fixed order-of-events issue where calculations containing the {coupons} were recalculated prematurely.

Fixed JS error where multiple forms were on the page and only one implemented GF calculations.