\documentclass[busletter]{newlfm}        %Renders correctly
%\documentclass[busletternofrom]{newlfm} %Renders incorrectly
\newlfmP{letrh=HEAVEN,addrt=SATAN}
\begin{document}
\begin{newlfm}

I don't want to talk to you no more, you empty-headed animal food trough
wiper! I fart in your general direction! Your mother was a hamster and your
father smelt of elderberries! 

\end{newlfm}
\end{document}