Current behavior:
When there are more than one images displayed, turning "WCS match" checkbox on will zoom and rotate all the images to the same pixel size and direction as the active image (selected, with orange color highlight), turning the checkbox off does nothing.

Improvement:
Turning off the "WCS match" should reset the images to a zero rotation.

Also include two bug fixes:

• A rotation issue: clicking rotate north on north up images fliped them south
• When north is up, clicking north up makes the image rotate south.