I think the spring is found behind one of the portals that you need the karma stabilizer to use. S3C is where you place the Secrets, and you need to use the AAA Battery in the ship to unlock it.
It would be nice if the "Squared" puzzles would autofill "9"s (and 6s on edges and 4s in corners). The big puzzles can get kind of tedious with them, and 0s already do something like this.
At a certain point we had to draw the line between ease of use and automation - we may consider adding the 9's as an option (defaulting to off) but 6's and 4's will likely never be automated.
if anything at this point i'd increase quest or other rewards before making quests faster