Prevent view to urlencode contextual filters
You need to use theme_links() function in template.php file of your theme. The original theme_links() function has this:

if (isset($link['href'])) {
  // Pass in $link as $options, they share the same keys.
  $output .= l($link['title'], $link['href'], $link);
}

You should replace it with this to undo the encoding:

if (isset($link['href'])) {
  // Pass in $link as $options, they share the same keys.
  $link_html = l($link['title'], $link['href'], $link);
  // Decode the link HTML before adding it to the output
  $link_html = rawurldecode($link_html);
  $output .= $link_html;
}