How should I say it...
The game was brilliant! Very good mechanics and very good forcing of puzzle solving. However my only real problem was 5M in which the ball would sometimes not even bother touching the portal. Other than that it was good.
Also a bit too frustrating especially near the end with the super low time limits and the timing to use the Time displacement. Very confusing combining both the time stop and reverse. Took me about a minute to figure that one out... In the end this is one of the best games I've ever played!