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Might not be much either, but maybe only the games in-which "unknown developer" wrote on the picture accompanied to the download page "this is not a screenshot"- are actually connected.

All in all, "this is not a screenshot" is written only on "On the Edge", "DPTG" & "Six Books" [the word "screenshot" is mentioned in "Tits & Boobies" and "en wye" though]

The solution Picture is 100x100 Pixels. The white dots may indicate symbolize a certain sequence of numbers or a code, in form of numbers. For instance, if the 70th pixel is the first white pixel to appear, the first number will be 70.

Update: it might actually be using steganography.

Using the different pixels some sort of a file might pop-up.

I didn't have any luck with the few free online steganalysis tools I threw at it, but I'm an utter neophyte in that area.