Thanks for the report. Current behavior is to support latex versions
of graphs by adding two "\usepackage" commands to the preamble. It is
possible tkz-arith.sty should also be added, and maybe something
bigger like tikz and pgf.
Also, the documentation could perhaps be improved by specifying just
what a tex environment needs to have so a standalone document will
compile when a sage latex-version graph is incorporated.
I don't think dvipng being present, or not, is relevant here, since
that merely affects if a PNG or PDF image gets created - it comes
after latex does its complaining.
Sample code below may help with understanding/debugging this
situation. This is now
<snip lots of latex graph code>