Don't know where is the problem, but
- uploading DJVU directly results in error (no log or anything)
- uploading from PDF results in a different error (log at https://tools.wmflabs.org/ia-upload/log/diccionariobiog02figugoog): LOG.CRITICAL: Client error: GET http://tools.wmflabs.org/phetools/pdf_to_djvu_cgi.py?cmd=convert&ia_id=diccionariobiog02figugoog resulted in a 400 Bad Request response: {"text": "invalid ia identifier, I can't locate needed files", "error": 2} [] []
except I can perfectly download and view without error the DJVU AND the PDF