Partial. Finished the second puzzle, not sure how to read the name of the puzzle from it.

I have solved both the sudoku and Yajilin alone, although the idea of transforming the grid into a Yajilin is jafe's idea. The solution to the Yajilin is

Worked Solution.

First, fill in any dead ends. The 4↓ and 3↑ have just one possible solution, and given that there must be a path adjacent to black squares, four portions of the loop can be filled in.
It is impossible for the two highlighted squares to both be black (as they share an edge), and if just one was black, it would create a dead end. Hence neither are black. Also, some other portions of the path have been filled in. The portion to the right of the 1↑ must be filled due to the 2↓ have already been completed.
The left-most 1→ has been filled, so the track can be partially identified along that row. Also, consider the 2→ along the bottom row. It is impossible for both black squares due to this 2→ to be to the left of the 1↑ (since that would result in a dead end), so there must be one square to the right of the 1↑. This area can thus be filled in.
The black square of the highlighted 1↓ must be at the top (since one below that would result in two adjacent black squares, and the one below that would violate the left-most 1→). More portions of the track can be easily completed.
Suppose the highlighted square is black. Then the grid must be completed as shown in grey, which will inevitably contradict one of the clues (probably the 1→). This is a contradiction, so the highlighted square is not black.
The squares featuring dots must contain a track (rather than a black square), which allows us to confirm the black square for the 1↑.
The path cannot follow the highlighted direction, as that would create two disjoint loops. We can thus connect the two sections of the track.
The remainder of the puzzle is trivial.

Partial. Finished the second puzzle, not sure how to read the name of the puzzle from it.

I have solved both the sudoku and Yajilin alone, although the idea of transforming the grid into a Yajilin is jafe's idea. The solution to the Yajilin is

Worked Solution.

First, fill in any dead ends. The 4↓ and 3↑ have just one possible solution, and given that there must be a path adjacent to black squares, four portions of the loop can be filled in.
It is impossible for the two highlighted squares to both be black (as they share an edge), and if just one was black, it would create a dead end. Hence neither are black. Also, some other portions of the path have been filled in. The portion to the right of the 1↑ must be filled due to the 2↓ have already been completed.
NB: As Stiv quite rightly points out, darkening only the right-hand square cannot be quite so succinctly eliminated. Luckily, it leads through to this position, from which it can be easily seen to be impossible. This is because the 2← requires an additional square. It must be the one on the right so as to not create a dead end for one of the three 'threads' in that region. However, placing it on the right leads to inevitably creating two distinct loops. The left-most 1→ has been filled, so the track can be partially identified along that row. Also, consider the 2→ along the bottom row. It is impossible for both black squares due to this 2→ to be to the left of the 1↑ (since that would result in a dead end), so there must be one square to the right of the 1↑. This area can thus be filled in.
The black square of the highlighted 1↓ must be at the top (since one below that would result in two adjacent black squares, and the one below that would violate the left-most 1→). More portions of the track can be easily completed.
Suppose the highlighted square is black. Then the grid must be completed as shown in grey, which will inevitably contradict one of the clues (probably the 1→). This is a contradiction, so the highlighted square is not black.
The squares featuring dots must contain a track (rather than a black square), which allows us to confirm the black square for the 1↑.
The path cannot follow the highlighted direction, as that would create two disjoint loops. We can thus connect the two sections of the track.
The remainder of the puzzle is trivial.

Partial. Finished the second puzzle, not sure how to read the name of the puzzle from it.

I have solved both the sudoku and Yajilin alone, although the idea of transforming the grid into a Yajilin is jafe's idea. The solution to the Yajilin is

Partial. Finished the second puzzle, not sure how to read the name of the puzzle from it.

I have solved both the sudoku and Yajilin alone, although the idea of transforming the grid into a Yajilin is jafe's idea. The solution to the Yajilin is

Worked Solution.

First, fill in any dead ends. The 4↓ and 3↑ have just one possible solution, and given that there must be a path adjacent to black squares, four portions of the loop can be filled in.
It is impossible for the two highlighted squares to both be black (as they share an edge), and if just one was black, it would create a dead end. Hence neither are black. Also, some other portions of the path have been filled in. The portion to the right of the 1↑ must be filled due to the 2↓ have already been completed.
The left-most 1→ has been filled, so the track can be partially identified along that row. Also, consider the 2→ along the bottom row. It is impossible for both black squares due to this 2→ to be to the left of the 1↑ (since that would result in a dead end), so there must be one square to the right of the 1↑. This area can thus be filled in.
The black square of the highlighted 1↓ must be at the top (since one below that would result in two adjacent black squares, and the one below that would violate the left-most 1→). More portions of the track can be easily completed.
Suppose the highlighted square is black. Then the grid must be completed as shown in grey, which will inevitably contradict one of the clues (probably the 1→). This is a contradiction, so the highlighted square is not black.
The squares featuring dots must contain a track (rather than a black square), which allows us to confirm the black square for the 1↑.
The path cannot follow the highlighted direction, as that would create two disjoint loops. We can thus connect the two sections of the track.
The remainder of the puzzle is trivial.