The click coordinates are stored within the HTML file (in the javascript). The map is thus generated locally with those coordinates directly in the <div> layer.
Hence why it can take a VERY long time to generate when you have a lot of clicks (browser might seem to freeze, especially in mozilla because it uses a slow method in that case; it works the fastest in MSIE as it is optimized for that).
In other words, you could just save the HTML page somewhere for safe-keeping. You could also printscreen and crop the image yourself if you rather have an image...
Although, having a list of the individual coordinates themselfs, in the right order, is a lot more usefull than having an image which will not show overlapping coordinates or a coordinate from the first week overwritten with a coordinate from the second week, etc...
This is way better than having an image!!
(You could always generate the image yourself using the buidlin list
And if you cba, you could even make a small php tool to upload the list and turn it into a real b/w image, for the "noobs", where they even could choose which week(s) they want, and/or directly overlaying the game pictures, or prizes, etc...
)
This said, my map doesn't have all the coordinates on it, it states "not all shown" and indeed not all coordinates are listed in the html. Most of the 4th week coordinates are missing
/ 
