Hello,
1) Could you, please, provide us with link to product where you added the gallery images but they do not appear?
Also, the product gallery was disabled via Screen Options http://prntscr.com/trlbij > http://prntscr.com/trlbof Try to add images now.
2) Because you hide it http://prntscr.com/trl9bz Remove the code to show the link.
Regards