Irregular background grid shapes - problem

Hello everyone.

I’m having a bit of a problem with arranging my photos against an irregular shape background. I tried to do it in different ways with the grid, but the photo does not line up or shifts when I turn on the preview. Do you have any ideas or advice on how to set it up?

Thanks for any help. Below is example a picture of the layout.

Here is my site Read-Only: LINK
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