MASSIVE SPOILER ALERT, DO NOT LOOK UNLESS YOU REALLY HAVE GIVEN UP
Full solution.
No words needed.
Actually, an explanation is in order. Basically, see the colour code? LEFT TO RIGHT is the logical order of the colours. E.g The blue stuff almost always relies on purple, etc. I did begin to run out of colours so some of the greys may be a little hard to distinguish. Red is most often explanation (I have tried to explain the non-obvious stuff, circled red stuff is a key deduction, and the circle near the seven links to the top left yellow thing), except in the grand finale (bottom right).
Click to see full size image
(Hopefully there are no mistakes)
Plus, the lines and text were fully hand-drawn for those of you who still appreciate hand-drawn art stuff. I seriously doubt that anybody is actually going to try reconstructing my solution, but if you have any parts that you don't understand - Please have tried thoroughly though, especially with all the previous colours - just ask me below.
This puzzle was well worth the effort! Very nicely done.