2013 Updates
https://www.codeproject.com/Articles/27431/Writing-Your-Own-RTF-Converter has more updates:
1th August, 2013 - v1.7.0.0 RtfHtmlConverter: Replaced align attributes with style attributes 20th January, 2013 - v1.6.0.0 RtfHtmlConverter: Added support for HTML tags superscript and subscript RtfImageBuilder.VisitTag: Fixed negative image dimensions by enforcing the absolute value RtfFontTableBuilder: Added option to ignore duplicated fonts RtfInterpreter: Added option to ignore unknown fonts RtfInterpreterSettings: New class to customize the interpreter RtfInterpreter/RtfInterpreterTool: Added support fo the interpreter settings Rtf2Xml/Rtf2Raw/Rtf2Html: New command line argument /IDF to ignore duplicated fonts Rtf2Xml/Rtf2Raw/Rtf2Html: New command line argument /IUF to ignore unknown fonts Rtf2Raw/Rtf2Html: New command line argument /UI to enforce unscaled images 12th September, 2012 - v1.5.0.0 ToggleArgument: Fixed parsing of the off-toggle RtfInterpreter: Allowed font with zero size RtfEmptyHtmlStyleConverter: New class with empty style converter Rtf2Html: New command line argument /IS to suppress inline styles using RtfEmptyHtmlStyleConverter