The solution to that problem varies from game to game, as I have not purchased the game, I cannot give advice on this matter. For me, I usually just search around in the settings looking for a resolution or fullscreen setting and adjust that accordingly. If you can't see the edge of the game, it is likely that the resolution is set for a screen larger than yours. Some flash games that I played have a similar problem, but they were designed for smaller screens.
I would recommend attempting to contact the developer with issues of screen resolution and device compatibility, as they would likely have far more insight than I do.