You may be lacking some font on your system. Try running with "Debug" checked; if, at the dvipng step, there is a prompt to install some fonts, follow the instructions to install the fonts, and you should be all set from there on.
You may be lacking some font on your system. Try running with "Debug" checked; if, at the dvipng step, there is a prompt to install some fonts, follow the instructions to install the fonts, and you should be all set from there on.