I've retrieved 'Gregs Crosshairs.scm.zip' and unzipped to /home/me/.config/GIMP/2.10/scripts/GregsCrosshairs.scm.
If an image is open, Image > Guides gives a menu with four options. New guide (by Percent)... New guide... New Guides from Selection Remove all Guides "New guide" allows creation of a horizontal or vertical dashed line at a specified fixed location. Can gimp have window sized crosshairs? Ie. horizontal and vertical lines intersecting at the mouse pointer hotpoint. Thanks, ... P. - mobile: +1 778 951 5147 VoIP: +1 604 670 0140