Can no longer add links to images
Design and Skin Customization
Bet its the HTML content in the editor.
GUESS: You've copy+pasted the contents to tinymce and there is other weird elements that came along for the ride. Something about those other html elements is preventing you from clicking on the image you want to link.
use the CODE button in the tinymce editor to see the HTML of that page to look for what the issue might be.
A way to test this is to open a new editor and add JUST an image and then try to link that. If it links, then the issue is not the linking, the issue is the content of the other editor.