I don't think there needs to be anything written on the control panel: the control panels on Garden Island, Selenitic, Amateria, Narayan, and Spire work fine without words.
I have a new set of ideas for a puzzle. The places on the map don't necessarily have to be in those places as long as they are all there.
Since the map could get confusing, I will explain how it works in the order the puzzles should be solved:
In the hut, there is a wall with "YI∩┟ΛΓΛ" written on it. An explorer does the lightning rod puzzle and opens the waterfall door as before. The rods, by the way, have ladders and platforms for maintenance. In the waterfall room is, besides artifacts, a lever that makes a light receiver go up through the ceiling and through the river above.
Around the island are light post which take in light of a certain color and shine in it a direction. The explorer must figure out the order of the colors to do this in (the order of "YI∩┟ΛΓΛ", since each symbol is for a color) and point the first post at the light receiver. Then, he must wait some amount of time and point it away. The receiver
must be pointed away from the receiver in order for the next post to work.
After the last post, the wall in the hut with "YI∩┟ΛΓΛ" on it will open and there will be more stuff behind it.
I don't know where to mention this, but explorers can swim, so there would have to be something stopping people swimming out too far. There could be a whirlpool like in Ahnonay or the explorer could Relto out just before being hit by lightning.
What's the IC purpose of Yinfara? Justintime9 wrote it to be a nice relaxing age. The natives used it to live on while they tried to figure out how to leave. That doesn't leave much in the way of an obvious "winning" ending, besides discovering secret rooms. The only thing I can think of would be to have the explorer escape the island the way the natives did, but with some restrictions so they can't go to far away.
EDIT:
For some reason the image got cut off. To see the whole thing you have to right-click on it and select "View Image".
To respond to your question:
I think the artifacts should not be in the hut. It gives the explorer too much for not having done anything. Obviously the hut should not be empty, but it should only contain things that would be in a hut. Temple things would be in the temple, and random other stuff that we have to figure out would be in the secret rooms. At the bottom of my map I listed some suggestions.
EDIT 2:
Also, the lightning rods would be much higher than everything around them. So the lightning rods would extend high into the sky so they could all be clearly visible from the control panel on top of the mountain.
Here is one thing a powered lightning rod can do: the hand-cranked one near the swamp could power the fence. Instead of a hole in the fence is an electrically-powered door which can only open when the power is on. Obviously this would not have been the natives' use for this rod (since the fence is modern, like the traffic cones) so there would have to be another use for it.
Oh, to clarify again: the name the natives called the island is not "Yinfara". We don't know what it is.
We call it Yinfara because the color symbols look like those letters. This is an explanation for how we know the island's name without knowing the natives' language. Now this makes me curious: where did the name come from OOC?