This framework is outdated and doesn't support all kind of files to upload, so i decided to fix the framework.
In the class Zend_Gdata_Docs
I did this by adding the entry JPG/JPEG/PPTX
private static $SUPPORTED_FILETYPES = array( 'JPG'=>'image/jpeg', 'JPEG'=>'image/jpeg', 'TXT'=>'text/plain', 'CSV'=>'text/csv', 'TSV'=>'text/tab-separated-values', 'TAB'=>'text/tab-separated-values', 'HTML'=>'text/html', 'HTM'=>'text/html', 'DOC'=>'application/msword', 'ODS'=>'application/vnd.oasis.opendocument.spreadsheet', 'ODT'=>'application/vnd.oasis.opendocument.text', 'RTF'=>'application/rtf', 'SXW'=>'application/vnd.sun.xml.writer', 'XLS'=>'application/vnd.ms-excel', 'XLSX'=>'application/vnd.ms-excel', 'PPT'=>'application/vnd.ms-powerpoint', 'PPTX'=>'application/vnd.ms-powerpoint', 'PPS'=>'application/vnd.ms-powerpoint');
It's working fine for the .pptx and for the jpeg/jpg the upload is working completely fine but once in Google Docs it is showing like a doc...