[NextGEN Slide.js] Sort order images inside galleries not working

I’m having trouble to sort order images with this plugin. No matter what kind of sorting for the images inside a gallery I select, the order that appears in the website is always filename / ascending order.

Even if I select all sorting on all galleries to be of another type, it still only sorts that way. If I change image orders by drag-and-drop, it also doesn’t work.

Looks like a bug. I’ve seen other topics on the same matter (https://www.ads-software.com/support/topic/plugin-nextgen-gallery-sort-order-in-gallery-not-working?replies=16), but they reference only NextGen, without the Slide.js, and their solutions have not worked for me.

Can you please help me?