How to get to Level 7
Observe that the Tree in level 6 and level 8 are the same. Now use the exit of the level 8 tree in the level 6 tree. (You can reach level 6 again either using the menu screen or that level 8 loops you back to level 1.)
How to get to S1
If a splitter has no where left to split, something magical might happen. This can occur in the beginning of level 10.
How to get to the S2 - Series
The similarity between Level 9 and S1 are not coincidental. Try walking the walk in Level 9 after getting to the exit. Another thing, because you will be going through level 9 a lot. You don’t need to solve the puzzel for a second time after unlocking the secret edge. You can just backspace into it.
How to beat the S2 - Series
If you get to S2g, the layout of the directional edges show in which sequenz you should traverse S2a - S2f. Die Spawnlocations and Colors (logo of the game) should be of use. Then a secret edge will appear in S2g.
How to get to the S4 - Series
Assuming you did the S3 series (good job, I accidentally made them very annoying), in S3c there is a disconnected path. The missing link appears when the counter strikes 0.How to get to level 11
At the bottom of level 10, you can force the merge to run out of options. So it will make some, thus temporarely clearing the used nodes. That should make the second exit accesible. Wished I could have used the machanic in later levels, but alas…
How to get to C1
In level 11 there was a color coded combination. If you use it in the S2 - Series, it will uncover a hidden path. You still need the other hidden path in S2g tho. Now you use that fact that the level progression loops. Going through S3, S4, back to level 9 and down to S2 again to insert the sequence and the oder path should have remain from the last round. (Tedious af, but not enough time to plan it better :( sorry). Nvm, just reset the S2 - Series on S2g and do it again with the other combination. (i just found out the other thing didn’t work, lesson learned, playtesting is important)