In trying to use feynmp to draw Feynman diagrams in LaTeXiT, I followed the instructions at http://osksn2.hep.sci.osaka-u.ac.jp/~taku/osx/feynmp_latexit.html and found it runs with no errors but does not produce any drawing. This problem has been encountered and discussed previously, see Use Feynmp to create feynman diagram in LaTeXiT, and the suggestion was to run preamble
\documentclass[10pt]{article}
\usepackage[usenames]{color} %used for font color
% !TEX program = pdflatexmk
\usepackage{amssymb} %maths
\usepackage{amsmath} %maths
\usepackage[utf8]{inputenc} %useful to type directly diacritic characters
\usepackage{feynmp-auto}
and the code
\begin{fmfgraph}(110,60)
\fmfleft{i1,i2}
\fmfright{o1,o2}
\fmf{fermion}{i1,v1,o1}
\fmf{fermion}{i2,v2,o2}
\fmf{photon}{v1,v2}
\end{fmfgraph}
\end{fmffile}
but I find that does not work for me. I have tried adding -shell-escape to the commands listed under Preferences > Typesetting, to no avail. I also do not know if I have to change some other settings to implement "% !TEX program = pdflatexmk". Any suggestions appreciated.