Please add precise pt by pt movement for shapes using the arrow key. Currently if move a straight line or a rectangular shape using the arrow keys, I cannot move it precisely where I want it to be, it just jumps a fixed distance or moves left or right. This is frustrating.
You take the problem from the wrong side.
What you want is to assign a precise location to your object relative to its anchor point.
Right-click on the shape and Properties from the contextual menu. The Type tab allows you to enter exact distances in the Position section. Don’t forget to select a meaningful reference position.
Be aware that any arrow key movement or mouse dragging will ruin your settings.
Also if your shapes are text boxes, you’ll be better off by replacing them by frames which can be controlled by a frame style.
Why can’t this just be done using the arrow key for any object?
Because it creates a dreaded direct formatting which conflicts with other internals.
Did you try Alt+Arrow?
And Shift+Arrow for large jumps.
For diagrams and similar, I prefer to create them in Draw and paste them as complete objects into Writer. They paste as a single object which makes anchoring easier, also Draw has more tools for drawings.
The arrow shortcuts work the same in Draw