I want to design a spacer pcb with no copper on either side
In the control panel, go to File -&gt; New -&gt; Board.

Now simply place four drill holes using the hole tool and draw your outline on the Dimension layer using a wire with a width of 0.

To make a hole of the desired size, simply type the size you want into the drill size box (you aren't limited to selecting values from the drop down).



Alternatively, once you have opened a new board, simply run the following commands:

grid inch 0.1 off;
Layer Dimension;
Set Wire_Bend 0;
Wire 0  (0 0) (2.5 0.7) (0 0);
hole 0.116   (0.2 0.2) (0.2 0.5) (2.3 0.2) (2.3 0.5);
grid last