II-4 is not nearly as hard when you realize that there are only 6 possible pattern: ↙↘↖↗ ↙↗↘↖ ↘↖↙↗ ↘↗↖↙ ↗↖↘↙ ↗↘↙↖
Additionally, if you start off by clicking the bottomleft or topright start as your first click, you get to know where the start is immediately. If it flashes red, the opposite corner is the start. If it flashes a different color, the bottomright spot is the start. If it shows as correct, the spot you clicked on is correct. I don't recommend this, but this means that if you are being click-efficient, you can solve each one in a maximum of 7 clicks. Because of how quick these are, it's really easy to get a lot of attempts in, which makes it much easier to get very lucky in some attempts. Here's a simple plan of action that works well:
↙↗↘↖↙↗
In 1/3 of cases, you win within 6 clicks with no reaction time needed. This also gives you the data to know exactly what the correct pattern at or before the fourth click. It's a good idea to watch to see if your first click flashes red because if you can react fast enough to the fact that it flashed red, changing your plan of action to:
↙↗↘↙↖
can boost your odds of winning immediately to 50%.
Ultimately the faster you can adjust to the information of which pattern is correct the better, but even if you don't, there's always a 1/27 chance that just ↙↗↘↖↙↗ instantly works for all three puzzles in the set.