This also allows the game to utilize and benefit from all the other improvements that were made for the newer games, resulting in a better experience.
As the Name implies, the game fits between ReThink 3 and 4 in terms of how the puzzles are designed, but it also comes with its own unique feature that is not in the newer games (yet).
Content wise, there are more than 40 puzzles in the game, all built around the utilization of lasers and logic.