Was it not just for screenshots? Have you tried;
⌘⇧3, for entire screen.
⌘⇧4, (for cross hairs with an area you drag across).
⌘⇧4, (for cross hairs with an area you drag across). Then press and hold ⇧ again to lock the Y axis.
⌘⇧4, (for cross hairs with an area you drag across). Then press and hold ⌘⇧ again to lock the X axis.