Sample run. Input:

Maze#.1,1-7,7
#########
#.......#
#.#.#.#.#
###...#.#
#...#...#
##.###.##
##...#..#
#######.#
#########
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Trailing newlines will confuse the noded code -- later I added a test for empty lines. Outputs:

(1, 1) (1, 2) (1, 3) (1, 4) (1, 5) (2, 5) (3, 5) (4, 5) (4, 6) (5, 6) 
+(6, 6) (6, 7) (7, 7)
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which corresponds to the path marked in ?:

#########
#?????..#
#.#.#?#.#
###..?#.#
#...#??.#
##.###?##
##...#??#
#######?#
#########
[download]

which is indeed the shortest path from (1, 1) to (7, 7). Note that there are walls around the maze; that is because the universe is toroidal in shape, that is, (0, 0) is next to (0, -1) which is the same (in this case) as (0, 8).

The maze header is simply "Maze", followed by the character for walls, the character for floors, entrance row, comma, entrance column, comma, dash, exit row, comma, exit column, newline.