Q: Export photos on to sd card using connection kit?

It doesn't look like that's an option at this point.  You can submit feedback here: http://www.apple.com/feedback/ipad.html

Because you can't. Apple has zero support for exporting files off your device.

You could see if your developing place has an app where you can upload the photos for them to print.

The camera connection kit can only be used to import photo/video files from a camera, SD card or USB flash drive. You can't import other types of files. You can't export any type of files using the camera connection kit.

 Cheers, Tom