There is alot of way to bypass the security check such as TOR for the simplest to avoid the IP check.
Another ideas to add for the updates is a countdown timer for each image. Since there is no countdown timer there, it it pretty hard to know the exact hour of the images.
The other thing will be to mark the pickxel which has expired for those contain a prize reward. Since not all user can read this (including I am)
Prize String (?): {(5,10,1.12),(22,11,0.29),(7,13,0.08),(7,11,0.08),(9,2,0.08),(5,15,0.08),(18,2,0.03),(1,10,0.03),(11,11,0.03),(9,15,0.03),(2,13,0.03),(6,10,0.03),(2,20,0.03),(5,6,0.03),(2,10,0.03),(12,11,0.01),(18,3,0.01),(18,4,0.01),(2,11,0.01),(7,4,0.01),(9,11,0.01),(6,2,0.01),(1,16,0.01),(1,2,0.01),(11,16,0.01),(12,2,0.01),(22,2,0.01),(2,16,0.01)}LkpJzwUMTfp23hiC
What do you mean? Do you suggest to specify in the prize string if the prize was taken (its pixel has been clicked by some user) or not?