You could try this:
Add a variable n, where n is equal to the max distance in the x or y direction that you want to change; in your example it would be 2.
>For "i" from -n to n
>For "j" from -n to n
->If loopindex("i") + loopindex("j") <= n, Set value at Xspawn+loopindex("i"),Yspawn+loopindex("j") to 1
>Set value at (Xspawn,Yspawn) to 16
That worked out really nice mate. Thank you!