At the end of a text block if you press Shift+RightArrow a critical error appears.
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System.ArgumentOutOfRangeException: lenght can't be less than zero.
parameter: length
in System.String.InternalSubStringWithChecks(Int32 startIndex, Int32 length, Boolean fAlwaysCopy)
in SMath.Control.TextRegion.()
in SMath.Control.TextRegion.GetSelectionStatus()
in SMath.Control.Worksheet.()
in SMath.Control.Worksheet.PageStatusManager(Boolean forced)
in SMath.Control.Worksheet.Insert(String value)
in ..(String )
in ..(String )
in ..(Keys )
in ..(Object , PreviewKeyDownEventArgs )
in System.Windows.Forms.Control.PreProcessControlMessageInternal(Control target, Message& msg)
in System.Windows.Forms.Application.ThreadContext.PreTranslateMessage(MSG& msg)[/quote]