If the conditional formatting is missing, the copy operation is executed with no errors.

Add support for custom document properties (CustomDocumentProperties).

Provide an option to change the display mode of the Worksheet to right-to-left.

Implement SMALL function (https://support.office.com/en-us/article/SMALL-function-17da8222-7c82-42b2-961b-14c45384df07 ), which returns k-th smallest value from a range:

SMALL(array, k)

Workaround: This could be implemented as a custom function: http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/custom-functions.html

Generating document which consists of merged cells in a row and some values then inserting a row on the top and then exporting the document or setting it to the RadSpreadsheet causes wrong merged cells.

If the generation is done on a workbook which is already set to the RadSpreadsheet everything is OK.

Workaround: The document can be exported and then imported again before the row is inserted.

When the column width is not an integer number, but a decimal fraction one, the width which is exported is not calculated correctly. 

For example, if there is a cell with some text and its column's width is autofit, it's exported with different actual width.

In addition, if the exported xlsx file is imported back in the Spreadsheet, the column width is a bit different from the one which was exported (only for the first export-import roundtrip).

Add support for TEXT function. The TEXT function allows changing the way a number appears by applying formatting to it using format codes.

TEXT(value, format_text)

A list of the supported functions is available at http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/functions 

This function can be implemented as a custom function. Check the following resources for more details on how to achieve that:

- http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/custom-functions 
- https://github.com/telerik/xaml-sdk/tree/master/Spreadsheet/WPF/CustomFunctions 

The MATCH function searches for a specified item in a range of cells and returns the relative position of the item found in this range.

A list of the supported functions is available at http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/functions

This function can be implemented as a custom function. Check the following resources for more details on how to achieve that:

- http://docs.telerik.com/devtools/document-processing/libraries/radspreadprocessing/features/formulas/custom-functions
- https://github.com/telerik/xaml-sdk/tree/master/Spreadsheet/CustomFunctions

Available in R3 2017 Official Release Version

Comparison operators (equal '=', not equal '<>') doesn't work as expected with references to empty cells. For example, expressions of type '=IF(A1="", TRUE, FALSE)' are evaluated to false when A1 cell is empty. 

In MS Excel, such expression is evaluated to TRUE if the cell is empty - i.e. empty cell value is considered equal to an empty string "".

Workaround: Use ISBLANK function if possible. Its results are consistent with MS Excel.

When a worksheet has name that has spaces and a hyperlink to this worksheet is being inserted in Excel, quotes are used to surround the name (ex: 'Sheet 12'!A1) for a valid hyperlink. If quotes are not added, the hyperlink is invalid.
In RadSpreadsheet, it is the opposite: (Sheet 12!A1 is correct, while 'Sheet 12'!A1 is incorrect).
Thus, opening such an exported document from RadSpreadsheet in Excel loads it with incorrect hyperlinks; and importing such an Excel document in RadSpreadsheet loads it with incorrect hyperlinks.

A way to workaround this issue is to modify the hyperlinks on import/export from/to RadSpreadsheet. You can find attached a project demonstrating this approach.

The AlternateContent element is used to store content which is not defined by the specification.

Implement text orientation for cell content import/export from/to XLSX format

Some documents containing a lot of worksheets with complex data and images cause slow importing and/or exporting.

When the cell content overflows the cell width the left cell border is not exported to PDF.

Enable the customers to import SVG images and use them in their documents.

The Open Document Format for Office Applications (ODF), also known as OpenDocument, is an open standard file format for spreadsheets, charts, presentations, and word processing documents using ZIP-compressed[6] XML files.

The most common filename extension for spreadsheets is .ods.

From the OOXML Specification: A comment is a rich-text note that is attached to and associated with a cell, separate from other cell content.

In Office 365 there are two types of comments:

• Comments/Notes
• Threaded Comments

This item applies to Comments/Notes only.

For Threaded Comments, please follow: SpreadProcessing: Comments (Threaded Comments)

When a chart is created with RadSpreadProcessing, by default it is exported with legend showing category list. If an xlsx file with a chart with legend showing only series is imported and exported, it will be changed to category list as well. API to switch between the two should be added.

Legend showing category list:

Legend showing series:

At this point XLS import of SpreadProcessing does not have support for notes/comments.

This is a sample code to replicate the error which is triggered on export: