Images do not show up in the File Slayer Library.

When accessing the File Slayer Library tab, File Slayer searches for file records directly. Salesforce requires the running user to either have explicit access to the files or have the Query All Files permission (usually reserved for System Administrators). 

Additional Considerations

Attachments are not supported in the Library, only Files.

In the File Slayer setup wizard, you can define the date range for files to be displayed. If files fall outside the defined range, they will not be displayed by default, but users can adjust the filters to refine their search.

If your files often come through email messages, you need to make sure that the Email Message Object is selected under the Object Settings in Setup. The same applies to other objects you're using that have files attached.

Files only show up if they are related to records that match the current filter criteria. For example, if you're running a filter to find files related to Case, including email messages, but the file is also linked to an Account, the file will now show up in the results.