anagram - A Page of Puzzling

I found this puzzle page from a newspaper and found it absolutely confounding. The sudoku had question marks and other things all over it, the logic puzzle made no sense, the cryptic crossword was missing any markings (and the clues weren't numbered, or in order!).

I thought I got my puzzling's worth out of the anagram, alphametic, and maze, until I realised there was something more fiendish going on here. I eventually managed to find a three word congratulatory message that was well hidden inside all these puzzles!

Can you solve all the puzzles and find the message?

NOTE: I've made a tiny tiny edit to the page. There were no mistakes in the previous page, the edit is practically superficial, but it might make the going a bit easier if you notice it.

Answer

The solution is

"Well done, love"

The crossword was first solved by @NeilW, and @Sconibulus solved the alphametic and the maze (go upvote them!).

For the Sudoku:

There are 8 question marks, which seem to correspond with the question marks in the crossword clues. Assigning each question mark the appropriate value, we get 5 1 7 6 2 3 1 4 (9) along the main diagonal.
The dotted line with the circle at the end is the same as the one in the logic puzzle, so the solution to the Sudoku will help fill in the logic puzzle.

For the Anagram:

The recent edit circled the page number, connecting it to the circles in the anagram puzzle. Due to @Arth, it can be translated to REMOVE ALL using the alphametic. We can then remove ALL from the letters, leaving us with E R W A F T.

For the Logic puzzle:

(After a nudge from the OP) The ostensible misspelling of "Margana" is actually an anagram of, well, "anagram", linking the logic puzzle to the anagram. Note also the ellipsis when Margana is about to say her type of number, and the ellipsis at the end of the anagram puzzle. We can't anagram the letters directly, but noting the strange discrepancy in font, we can actually rotate the W to become an M, giving us FERMAT.
Using this, we can deduce that the numbers have to be:
- Mersenne: 31
- Perfect: 496
- Fermat: 257

Back to the Sudoku:

The "correct" solution to the Sudoku, then, would use those numbers along the dotted line. If we try to solve the Sudoku with the numbers given, we get a 7 in the box in row 5 and column 6. This allows us to fill in the numbers on the dotted line by deduction, ordered 31, 257, and 496.
From here, we can solve the grid (thanks @LeppyR64 for solving a critical step in the sudoku!):

Finally to the Maze:

The maze looks just like the Sudoku grid, suggesting that we can overlay it onto the Sudoku (as @Sconibulus suggests). Note that "jump from an arrow" is underlined, hinting that the code from the alphametic should be applied to the squares where we made a jump. The numbers in these squares, in order, are: 6, 7, 8, 8, 2, 4, 1, 7, 8, 4, 3, 7. If we then apply the alphametic code, we get WELLDONELOVE, which clearly leads to the solution.