G'evening Rel and welcome to the forums

there is an issue with click-drag on a second screen in wow. basically, blizzard moves the cursor outside and to the left of the current wow window. when that happens, and you let up, there is a brief moment that blizzard has not moved the mouse back to the original spot on the original window. if that occurs, and you have focus-follows-mouse enabled, then keyclone will push focus to the underlying wow window.... and the button-up event never goes into the original wow.

when that happens, and you try to move your mouse back, wow still thinks your mouse should be outside to the left... and will move your mouse there. it's very annoying and i am trying to find a work around (should be available on the next release)

if it becomes too unbearable, uncheck focus-follows-mouse and that should resolve the issue

have a good night,

Rob (keyclone developer)