The demo works correctly. I suppose that you are having a problem since you just added a file to the upload queue (clicked Add Files/ Añadir ficheros) and did not really upload the file after that -- you need to click the Upload/ Añadir button on the right side of the Upload Panel when you are finished with the upload queue. This is to make it possible to select multiple files and upload them in one go.
Re: CkFinder 2.1 demo does not work?
Hope this solves your issue.
Documentation Manager, CKSource
See CKEditor 5 docs, CKEditor 4 docs, CKEditor 3 docs, CKFinder 3 docs, CKFinder 2 docs for help.
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