The number of actions that can be undone via the Edit/Undo-Redo commands.
Valid range: <2, 200>
Default: 20

Notes:

• If you set a very high undo level and copy/paste very large amounts of data, the system memory usage may jump significantly as well.
• The drag-drop copying is treated as a two-step action so the minimum undo level is 2.

The number of data 'slots' that can be filled cyclically via subsequent copy operations.
Valid range: <1, 16>
Default: 1

By default, the Edit/Paste command inserts the last copied data. To paste any data available in the Copy/Paste buffer, click the arrow button associated with the Paste button and choose the data item to paste:

Specifies which formula notation should be used when saving newly created *.ods files.
You can choose one of the following formula "namespaces":
Excel 2010/2013,
OpenFormula,
Google Docs.
When editing existing *.ods files GS-Calc preserves their current formula notation. To change it you can use the Save As command.
Saving a file with the right formula namespace might be important because opening an ODF file in other applications that don't support it might result in removing the formulas and replacing them with their current values.
Default: Excel 2010/2013

If this option is on, GS-Calc tries to identify the style of each newly entered data and changes the previous cell format if it's different.
Default: On

If this option is on the system "Date Picker" control is displayed when you edit cell containing dates.
For more information on using the date picker, see: editing and filling cells.
Default: On

If this option is on text strings representing dates will be converted to date serial numbers only in cells having the Date, Time or Date/Time format set.
Default: Off

If this option is on formulas edited in cells will be displayed using syntax coloring. Cell references, strings and errors will be displayed in various colors and/or using various font attributes. This functionality is provided thanks to the © Scintilla project.
Default: Off

Specifies whether absolute cell references like $A$1 in formulas should be modified when copying cells and inserting/deleting columns/rows.
Default: Off

Specifies whether relative cell references like A1 in formulas should be modified when copying cells and inserting/deleting columns/rows.
Default: On

Hides cell markers that are normally displayed in cells which contain formulas, drop-down lists, comments, circular references (>1) and truncated text.
Default: On

If this option is on, GS-Calc displays a progress bar when saving and opening files.
Default: On

Displays formulas instead of their values.
Default: Off

Changes the current cell address notation. See: Cell references.
You must use the current notation when entering formulas. Note that this doesn't affect existing/saved workbooks - internally, always the A1 notation is used.
Default: Off (Use A1)

Adds the 3rd "undeterminate" button state for toolbar formatting buttons.
By default, if a range is selected the button states reflect the binary format/state of the top-left cell of the selection, e.g. "Bold" or "Not Bold". With the above option selected, the entire selected range is checked and if that range contains e.g. both "Bold" or "Not Bold", the button is set to the "undeterminate" state.
Note: Choosing this option may significantly slow down selecting very large ranges. Default: Off

If this option is turned on, after opening a text or xBase file all not empty columns will be automatically resized to fit their widths to their contents.
The resizing is performed within the limits defined by the <AutoFitMin> and <AutoFitMax> elements in the GS-Base settings.xml configuration file. By default these values are equal respectively to 20 pixels and 640 pixels and they can be modified within the <2; 2000> range.
Note: Choosing this option may slow down opening very large text and xBase files.
Default: Off

If this option is turned on, the Chart dialog box is closed when you switch to another worksheet.
Leaving that dialog box opened is helpful if the chart resides in one worksheet and its data is selected in another.
Default: Off

Specifies whether and how truncate the text which is longer that the cell width.
Default: Allow if adjoining cells are empty.

Specifies whether GS-Base should scroll back to the cell where selecting cells started.
If this option is turned off, to scroll back to the selection origin, click the address displayed on worksheet window toolbar.
Default: No action

Specifies how GS-Base should react to a single mouse wheel move. Available options are:

• scrolling lines,
• scrolling pages.

Default: Scroll lines

Specifies whether (and how) the current position should be scrolled after you finish editing a given cell and press Enter.
Default: No action

Specifies the folder displayed in the Open File dialog box when you open it for the first time (after launching GS-Calc).

Specifies the period of user inactivity after which GS-Calc will automatically save all open workbooks.
Default: Never

Specifies the period of user inactivity after which GS-Calc will automatically close all open workbooks. If any of the workbooks was modified, it'll be saved before closing.
Default: Never

Specifies the opacity of dialog boxes. Decreasing this value means making the windows more transparent.
Valid range: <10, 100>
Default: 100% (no transparency)

Specifies the default font name.
Default: Arial

If there are circular formula references in a workbook, this parameter specifies how many such circular iterations should be performed when the workbook is updated. The default value of 1 means that after detecting such a cycle GS-Calc stops and exits such a calculation loop after detecting it. Circular cell markers are displayed if level >= 2.
To list all formulas with circular references, use the "Inspect Cells" pane and click the "Add" button.
Valid range: <1, 255>
Default: 1

If this option is on, GS-Calc updates formulas using processes running in the "background", that is, not blocking any other GS-Calc's functions. Updated results of formulas become available only after the procedure finishes. It's not possible to end up with or use partially updated data.
Actions resulting in modifying cell data causes restarting of the active update cycle. Other actions, including formatting, don't have any impact on background updating.
The status bar shows the progress bar for the current re-calculation process and the total number of active processes.
Background updating requires more memory than the non-background mode. Default: On

If this option is on and cells contain references to external workbooks, GS-Calc will open and retain such workbooks in memory until the referencing workbook is closed. If this option is off the referenced workbooks are open and close each time a referencing cell is updated during the calculation process/loop.
Default: On

Specifies the number of CPUs/threads to be used when updating formulas, auto-fitting column widths and performing some editing actions. If two or more processor cores are available, allowing GS-Calc to use them will result in faster recalculation.
Choosing a value that is greater than the actual number of cores of your processor doesn't improve the performance.
The value specified here is used by workbooks that have their individual Number of CPUs option set to Default. You can overwrite this value for each workbook.
Default: 2

Specifies the priority of the update threads. The available priority classes correspond to the standard Windows settings for threads.
Note that choosing the highest priorities can significantly hamper all other processes in your system.
The value specified here is used by workbooks that have their individual Threads priority option set to Default. You can overwrite this value for each workbook.
Default: 2

Forces re-calculation of the entire workbook after each cell editing action.
The value specified here is used by workbooks that have their individual Update Mode
option set to Default. You can overwrite this value for each workbook.
Default: on

Optimizes the calculations assuming that most of the formulas use both compound built-in functions and references.
The value specified here is used by workbooks that have their individual Update Optimization Options option set to Default. You can overwrite this value for each workbook.
Default: on

Optimizes the calculations assuming that worksheets contain short calculation chains (groups of linked cells).
The value specified here is used by workbooks that have their individual Update Optimization Options option set to Default. You can overwrite this value for each workbook.
Default: on

Recalculates cells/formulas moving from the right to the left and towards the top.
(The opposite order the default.)
The value specified here is used by workbooks that have their individual Update Optimization Options option set to Default. You can overwrite this value for each workbook.
Default: off