only slightly different, just to see some pages;
cow.pdf must be in the same folder of  test.tex

%%
%%
%% test.tex
\setupcolors[state=start]
\setupinteraction[state=start]
\starttext
\startfrontmatter
\completecontent
\stopfrontmatter
\startbodymatter
\chapter{Chapter}
\section{Section}
\input tufte
\externalfigure[cow]
\chapter{Chapter 2}
\section{Section}
\input knuth
\stopbodymatter
\stoptext