In case you still are trying to fix this or someone else runs into the same issue, modify modality-functions.php in your themes/modality/functions folder with the follow:
insert the following 3 lines at line 14, after function modality_setup() {
add_theme_support( ‘wc-product-gallery-zoom’ );
add_theme_support( ‘wc-product-gallery-lightbox’ );
add_theme_support( ‘wc-product-gallery-slider’ );
