Clicking MARK
saves the current position in the series of drawing steps that
you have made.
Clicking UNROLL
undoes ALL of the drawing steps made since the most recent MARK
command.
Clicking CHECK
checks whether the lines you have drawn make up the loop that
solves the puzzle. This ignores any Xs drawn and any coloring
you made.
Clicking EDIT
opens an editing box that displays text defining the squares
of the puzzle:
Each line of the text represents a row of the puzzle.
The digits 0,1,2,3
in the text represent squares with those numbers in them.
The letter w
(think -W-hitespace) represents a square with no
number in it.
The editing box has buttons to accept any changes you make
or to cancel them.
Clicking PASTE
is similar to EDIT but replaces the text with the clipboard content.
You should drag and select appropriate text
(describing a slitherlink puzzle)
from some other source (email or web page) before using this button.
Clicking MAKE
creates a new puzzle of specified size and difficulty.
Details.