(Part 0 [hints])
Part 1 [pictures of fish]
Part 2 [weird capitalization]
Part 3 [flags]
Part 4 [word search]
Part 5 [grids]
Part 6 [lines of text]
Part 7 [diagrams]
Part 8 [candy]
Part 9 [meta]
Thanks to Stiv, Gareth, and samm82 for correcting a few errors and helping to finish off the puzzle.
Very Partial Answer
I think I've got the gist of what's going on so maybe if I post what I have so far, it may inspire somebody else.
I have no idea about the street names on the map
Song Ideas (credit to MacGyver88 for figuring out the idea behind this)
Solving the rest
The first thing we need to do here is rearrange the 30 tiles in a meaningful way. We can do this by noticing:
What do we have here? Look next at the numbers in the first four columns. These look a lot like:
What might our desired 2-word 10-letter answer be? Well, what do all these people have in common?
Alaiko did all the legwork and the OP gave pretty specific hints, so I don't want any credit for this, but it seems that if flag 2 is something like Yugoslavia (maybe these names are interchangeable? I'm not very familiar with European political history. Or maybe an older flag-I see at least one green Yugoslavia flag on the internet, or some other land ...
OK, here's my best guess.
The picture of the raised fist with the medal represents
The 1 in the corner of that represents
The letters on the right hand side of the + sign represent
Based on the second hint we are actually looking for
Adding these together, we get the left hand picture with 2 in the top right representing
Then the right hand picture with ...
This is probably simply called an edge-matching puzzle (also known by various names such as Tetravex). The puzzle is in general NP-complete (i.e. not easy to solve in general cases), but the algorithms for solving do exist (e.g., Douglas-Rachford algorithm, but unfortunately I don't know the details).
It is fairly straightforward to deduce a solution.
If you permute the rows of a solution it remains a solution, and similarly you can permute columns.
An alternative is to start with a filled grid, and then place the 6 blank spaces, also using an even number in each row and column.
I believe the number in the middle (position 1) should be 128, this doubles each iteration. This number should be enclosed by a square. Outside this square, there should be two squares/dots on each edge (in positions 2, 3, 4 and 5). One final square should enclose the entire system, and there should be no squares/dots in positions 6, 7, 8, 9.
This pattern is only almost exactly the same that HTM and Jaap already posted, but the approach may be of some interest. Or then again, it may not :-)
To find this solution, I first flipped the puzzle over: a full grid satisfies the parity condition, so instead of 10 crosses, we can just do the puzzle with 6. Any solution for 6 will automatically work for ...
My answer is D as well but I got to it slightly different way.
From right to left number of small, quarter, squares increases by 1 every step and colours get negated every step. So it looks like that (w for white and k for black background):
'squares': (?) 4 - 3 - 2 - 1 - 0
'background': K - W - K - W - K
So there are four squares on black background, ...