Installing Theme from uploaded file. Not uploaded theme?

You need to set the permissions locally in a UNIX environment:

sudo chown -R www-data:www-data /usr/share/wordpress

Also perhaps:

chown -R nobody:nobody /path/to/wordpress

Also try setting the FTP creds in the wp-config.php file:

define( 'FTP_USER', 'username' ); 
define( 'FTP_PASS', 'password' ); 
define( 'FTP_HOST', 'ftp.example.org:21' );

Use “admin” or “root” for user and leave the password blank.