Currently, there is no way to set or get this underline type.
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The fix will be available in our official release Q3 2015 SP1.

The fix will be available in our LIB release (v. 2016.01.0312).

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First column of the pivotgrid has width based on the header (see attached screenshot). It's obvious that the header should span between columns.

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This item is migrated to the Telerik Document Processing portal: 
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Workaround:
Copy the default styles after the Mail Merge

RadFlowDocument merged = sourceDocument.MailMerge(mailMergeSource);
merged.DefaultStyle.ParagraphProperties.CopyPropertiesFrom(sourceDocument.DefaultStyle.ParagraphProperties);
merged.DefaultStyle.CharacterProperties.CopyPropertiesFrom(sourceDocument.DefaultStyle.CharacterProperties);
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If the value from the source contains new lines, they should be inserted in the resulting documents as new paragraphs.
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When defaultThemeVersion is missing from the file, some styles are not shown when the document is opened in MS Excel.
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http://feedback.telerik.com/Project/184/Feedback/Details/190098 
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This item is migrated to the Telerik Document Processing portal: 
http://feedback.telerik.com/Project/184/Feedback/Details/190099 
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This item is migrated to the Telerik Document Processing portal: 
http://feedback.telerik.com/Project/184/Feedback/Details/190101 
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Available in LIB version 2016.1.118, it will be also available in the 2016 Q1 SP Release.

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When the last element from a table cell is an empty line, the latter is skipped and not imported.
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http://feedback.telerik.com/Project/184/Feedback/Details/190106 
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Add support for MID function:

https://support.office.com/en-us/article/MID-MIDB-functions-d5f9e25c-d7d6-472e-b568-4ecb12433028

MID returns a specific number of characters from a text string, starting at the position you specify, based on the number of characters you specify.

MID(text, start_num, num_chars)
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