Hello, in Simple Image Gallery Pro when you publish several galleries on the same page if you expand an image and continue to see the next images shows all the galleries followed one behind the other,

Highslide has a "hs.slideshowGroup" option that allows you to separate the visualization of the galleries, I have seen that the code of Simple Image Gallery is something different from the one of Highslide, I can modify the code of the Sleek template to show the separated images in galleries ?

highslide.com/ref/hs.slideshowGroup

hs.slideshowGroup
Places your popups into groups for Next and Previous navigation.

<a class = "highslide" href = "full1.jpg" onclick = "return hs.expand (this,
{slideshowGroup: 'first-group'}) ">
<img src = "../ samples / thumb1.jpg" alt = "" />
</a>

The implementation should be a bit different.
You need to use multiple galleries. Each gallery can have its own settings, including a different lightbox.

Since this is related to a commercial extension, please open a ticket so we can sort this out.