The format string for dates should be in lowercase so they can work as expected. Ensure this in the internal logic.
Introduce support for cell reference ranges which refer to whole columns. For example "=Sheet1$A:$A" refers to the whole column A.
When defaultThemeVersion is missing from the file, some styles are not shown when the document is opened in MS Excel.
When I need to populate a cell that I find using a DefinedName I should parse RefersTo to get Worksheet name. But DefinedName class contains Scope property which has CurrentWorksheet and Workbook properties (internal). It would be very useful if these properties could be public.
The item is closed as duplicated of https://feedback.telerik.com/Project/184/Feedback/Details/190065-spreadprocessing-implement-right-to-left-direction.