jumpy
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When you export a JSON file, whether you're downgrading or not, you're creating assets for use in runtimes. If the "Pack" option is selected, the images are optionally combined into an atlas image.
When importing a JSON file into Spine, you're only importing the skeleton data, not the images. After importing the JSON, you need to save the project and select the image folder from the previous project (or another folder containing the same images with an identical structure).
You can find the image folder path under the skeleton tree as shown in the image below:
As Spinebot suggested, if the path structure of the image has changed, you can use the Find and Replace function to modify the image paths in batches.
