Also there is an issue in the snippet coding, when you have variation.
If i have a min price of 100 EUR and a max price of 200 EUR, it will report 100-200 EUR in the price schema attribute. This is causing an error in the google webmaster tool : Erreur : Incomplete microdata with schema.org.
in order to not trigger this error which is avoiding the snippet to shows in the SERP, you will have to use :
<div itemprop=”offers” itemscope itemtype=”http://schema.org/AggregateOffer”>
<span itemprop=”lowPrice”>$1250</span>
to <span itemprop=”highPrice”>$1495</span>
But i have no idea on how to call those attributes with PHP. If you could provide some custom PHP and notified the dev for the next updates it would be awesome !
best regards