Import a Look recipe, not a project or photo
The inspected Neko Photo Looks panel imports and exports .look files. A Look is JSON with an id, name, editing params and optional tags/timestamp. It carries a recipe, not the source photo.
If your installed build has the Looks panel, choose its import action and select the downloaded .look file. Review the recipe before applying it to the current image or batch item. Apply only to a copy while learning; the same parameters produce different results on different images.
The website accepts a conservative subset of this real format: basic filters, exposure, levels, shadow/highlight and known built-in LUT references. It rejects project data, masks, image payloads, external paths and unknown fields. Rejection by the website does not mean every advanced desktop Look is invalid; it means that payload is outside the portal's curated safe subset.
The original Gentle Tone recipe contains only a small exposure/contrast/saturation adjustment. Check its version label rather than assuming every historical installer supports Looks.