Ben, once you have the co-ordinates this is what you have to do:

something like

if x = 0000 and y = 0000 then
display/change what ever you want
else
if x = 1111 and y = 1111 then
display/change what ever you want
else
etc
etc
etc

0000 and 1111 are just examples these would really be like 2367 or 6534 etc
Rememember?