Have you also tried increasing the max width and max height to 2048 instead of 1024? I suspect your stick_3 and stick_4 may be too large if it has the additional padding.
Also, avoid using filename_#.png naming scheme. Spine atlases attach a special meaning to the _# at the end and you may end up with problems when you import them in your game engine. -# is fine. Even spaces is fine.
I'm not sure if this is why you're getting the error. Probably not.
