Answer

If you want to link a thumbnail:
- Make sure that the option "do not include in the lightbox" in Unchecked, so that option should not be checked.
- Use the hyperlink panel to link the thumbnail to another page.
Note: When you link a thumbnail to another page, the thumbnail's video/image will not be included in the lightbox. For example, lets say you have 3 thumbnails and one of them is linked through the hyperlink panel, then the image or video in that thumbnail will not show up in the lightbox, so when you click on one of the two other thumbnails and lightbox opens, then you can see only the video/image in those two and the linked thumbnail's image will not be included.
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If your grid is not keeping the proportion properly, you need to:
- Make sure that you entered the right number of largest/first breakpoint in the MAIN widget option panel, and make sure that you do not have ore than one copy of the MAIN widget, not matter how many thumbnails you have.
- If you have breakpoints in the Master page that is applied to the page, you can see the notions of that master page in your breakpoint bar, as small white triangles, then you need to create breakpoints on the exact places where you have those notions, no matter if you do not make any changes, then change the proportion to what you want in those breakpoints.