We have released version 1.2 of MindFusion.Spreadsheet for WPF. The new version includes:

UI Localization
The standard forms from the MindFusion.Spreadsheet.Wpf.StandardForms.dll assembly can now be localized using XML files that map interface element identifiers to strings. To load a localization file, call the new SetLocalizationInfo method of the Workbook class passing the file path as argument. Ready-made localization files for French, German, Chinese, Korean, Spanish, Portuguese and Russian are provided in the Localization folder under the component's installation root.

Grouping and Outlining
Rows and columns can now be grouped. To group or ungroup a range of rows or columns, use the Group or Ungroup methods of the RowRange and ColumnRange classes. To set the outline level of a row/column or a range of rows/columns directly, use the OutlineLevel property. Groups can be expanded and collapsed interactively, by clicking on the expand/collapse button in the view, or programmatically, by settings the IsCollapsed property of the respective row or column.

New Events
Several new events have been added to the WorkbookView class: ColumnGroupCollapsed, ColumnGroupExpanded, ColumnOutlineLevelToggled, RowGroupCollapsed, RowGroupExpanded, and RowOutlineLevelToggled.

The latest version can be downloaded here:
http://mindfusion.eu/WpfSpreadsheet.zip

The component's assemblies are also available as Nuget package. To install it, run the following command in the Package Manager Console:
PM> Install-Package MindFusion.Spreadsheet.Wpf

Enjoy!