Solved
Can't save Carousel Set
Can't save Carousel Set because seems error, this error always appears.

Can't save Carousel Set because seems error, this error always appears.

Have you tried the following:
1. Create a carousel set with multiple image.
2. Use an existing preset and try to save the carousel set.
Seems like a new user preset library isn't available in your case. You might want to try with a vanilla AEM instance and DM config.
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