There is a bug in your swatches plugin. Two actually. If you select Default Form Values under variations something other than the main product image it will not show the main product image in the thumbnails until you click on the swatch.

So, if you set an color from the gallery images it will not show the main product image in the thumbnails.

Second if you select Default Form Values for example color and size it will set the size as active but not the color as active on the product page.

I’m interested in your plugin.
I note that the swatches can be used to show out of stock items. (red line through swatch).
Can it also be used to highlight those items “On back-order”?

Kind regards

Bill