What's your PDF viewer? Look at it in the free Adobe Reader. Many third-party PDF readers don't preview or handle PDF forms and annotations correctly (e.g., Apple Preview).
You posted this in another forum and I responded. Both Safari and Chrome have their own buggy and incomplete PDF viewers that don't support the full PDF imaging model (including forms). Chrome can be configured to use Adobe Reader or Acrobat if installed. I don't know about Safari.