The main menu "Options" offers the following options which are saved when the Sudoku program is closed:
Track: If checked, the program displays the solving process.
Find all Solutions: If more than one solution is possible for the current problem the program calculates all solutions. When finished, the first 100 solutions can be examined using the "<"-button or ">"-button respectively.
Show Possible Values: If checked, the grid contains "Watch Hand" hints.
Auto Check: If checked, the program checks whether or not the resulting problem is still solvable after keying in a new value.
Mark Neighbors: If checked, the neighbors of the current cell are highlighted with a different color.
In addition this menu offers two entries to control the solving time:
Pause: The solving timer is stopped until the next value is entered or changed.
The "Generate" option page offers the following options:
Use Precalculated Problems: If checked, problems are not newly generated but loaded from sudoku.pi-c-it.de (for both normal and X Sudokus approx. 25 000 precalculated are available). With this option checked, the "generation" of new Sudokus only takes a very short moment. If checked and an internet connection is not available, this option is ignored and the problem is generated locally. To prevent an overload of the remote site, the maximum value for problems in new booklets is set to 16 if the option is checked.
Minimum Number of Values in generated Problems: This value must be between 17 and 35. Even though there is no proof that Sudoku problems must contain at least 17 numbers, nobody has ever generated a problem with less values (in 2011, a "Brute-Force-Search" found no valid problem with less than 17 number, see here). The generation of problems with more than 35 values is very complex, therefore the upper limit is set to this value. This option is not available if "Generate Minimum Problems" is checked.
Generate Minimum Problems: If checked, the new generated problems are minimized (see "Minimal Problems").
Severity: The severity level of generated problems. This setting is also used for the selection of existing problems when a booklet is generated out of existing problems.
Select Level: If this option is set, the severity level can be selected prior the generation of a new problem. Otherwise the severity level of new problems is randomly selected out of the levels checked in this dialog. This option does influence the severity level of the problems in booklets.
Sudoku Types for Booklets: Option to set which types of Sudokus are generated for new booklets. If both types are checked the respective count is at random.
New Problems: The number of problems in new generated booklets.
Existing Problems: The number of problems in booklets generated out of existing problems. If the checkbox "unlimited" is checked all problems of the selected directory and all of its sub folders will be used for the booklet.
Auto Save Booklet Problems: If checked, problems generated for new booklets are automatically stored in a sub folder of the "Problem Directory". The name of this sub folder is made up of the current date and time.
Problem Directory: Problems are stored and loaded from this directory by default. This folder can changed by clicking the "..."-button.
The "Sudoku Options" dialog can be opened by selecting the menu item "Options|Sudoku Options". The first option page "Screen Layout" offers the following items:
Language: Switch the language of the user interface between English and German.
Contrast: Adjust the contrast between the individual 3*3 squares. The contrast of the diagonals in X-Sudokus is also depending on this value.
Size: Adjust the size of the user interface.
Hide when minimized: If checked, the Sudoku taskbar button is hidden when the Sudoku application is minimized.
Save State: If checked, the status of the current Sudoku problem is saved when exiting the application
Possible Values: Sets how calculated possible values or "candidates" are displayed or printed out. However, if there is not enough space to print digits, the "watch hands" are used for the print out. This restriction is not necessary for the display on the screen.
The "Print" option page offers the following options:
Print Solutions: If checked, the solutions of the problems are printed out. If only one problem is printed out, the solution is printed right to the problem, otherwise (in case of printing out problem booklets) the solutions are printed on extra pages. In either case, the solution is printed upside down (with that, cheating is not that simple...).
Print Possible Values: If checked, the printout contains the possible values either shown as "Watch Hand" hints or as tiny numbers. Which of this is used depends on the respective option and the size of the printout (for very small printouts tiny numbers aren't readable, in that case the watch hands are used indepently of the current setting of the option). If the current problem contains candiates, the user is asked before the printout starts whether she wants the candidates or the possible values to be printed out.
Size - Problem:
Large: One problem horizontally.
Normal: Two problems horizontally.
Small: Three problems horizontally.
Tiny: Four problems horizontally.
Size - Solution:
Normal: Four solutions horizontally.
Small: Five solutions horizontally.
Contrast for X-Sudokus: Sets the contrast of the "X" in the printout of X-Sudokus. A value of 20 should be suitable for the most printers.
Print Internal Severity: If checked, the internal used number to determine the severity level is printed out below the problem.