turning the dial 59 steps should be right
We will look at the bottom four pictures numbering them from 1 to 4.
First number 3 (the stone):
The Symbols on the stone are mathematical formulas in unary system. (only counting ones)
Each vertical line $|$ is a one and for each single number you simply count the vertical lines.
Each two horizontal lines $=$ is an addition symbol.
Each square $\square$ is a multiplication symbol.
Each T-like symbol $T$ is an equality symbol.
Therefore we get the following equations:
$$2=2$$
$$3=3$$
$$1+3=2+2$$
$$2\times2=2+2$$
$$1\times4=2\times2$$
Next is number 4 (the plate):
This is a mathematical term.
First we have to calculate the corners with the respective mathematical operators.
Corners 1 and 4 (counted left to right, top to bottom) are products of something.
Corners 2 and 3 are sums of something.
Next we go one step to the middle.
Corners 1 and 2 are added to get the top half.
Corners 3 and 4 are multiplied to get the bottom half.
Finally the top and bottom half are added.
We get the following term.
$$((1_a\times1_b)+(2_a+2_b))+((3_a+3_b)\times(4_a\times4_b))$$
But where do we get the numbers to put into this term.
In picture number 1 (the hill) we can see stones that have numbers in the same unary system as in picture 3 written on them.
We can also see a pedestal. The same pedestal as on the plate in picture 4.
In picture 4 however the pedestal is on the right side of the plate so we have to imagine the stones in picture 1 rotated by 180$^\circ$ as if standing on the other side.
With this we can see the needed corners.
Corner 1 is 5 and 6
Corner 2 is 7 and 8
Corner 3 is 3 and 4
Corner 4 is 1 and 2
Lets fill in the term.
$$((5\times6)+(7+8))+((3+4)\times(1\times2))$$
$$=(30+15)+(7\times2)$$
$$=45+14$$
$$=59$$
Therefore I think that the dial has to be turned 59 steps.
As for the symbol in picture 2 I think it is a red herring and has nothing to do with the dial since i was not able to think of anything it could be used for.