And find this CSS rule:
Delete this CSS rule, completely.
Because it is effecting our product slider module, and it also has display:hidden rule, which hides the items in the slider.
I also notice a JAVA conflict issue in your website which is created by this JS file: NivooSlider.js
I believe it is the slideshow you are using. For testing purposes, unpublished that and try again. If still no luck, then try the another module position. Lets say, try the "horizontal" layout..
Try my suggestions and then let me know.
Flexible Support Team.
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