Follow this guide:
make the following changes to /etc/nxserver/node.conf file:
AGENT_EXTRA_OPTIONS_X="-fp /usr/share/fonts/X11/misc/,/usr/share/fonts/X11/75dpi/:unscaled,/usr/share/fonts/X11/100dpi/:unscaled,/usr/share/fonts/X11/Type1/,/usr/share/fonts/X11/100dpi/,/usr/share/fonts/X11/75dpi/"
Note: Although this looks like multiple lines, this is actually one long line in the conf file. The directories you specify here vary according to the fonts you have installed. Just do "ls /usr/share/fonts/X11" to figure out what you need.
Also made the following change in the node.conf file:
COMMAND_XAUTH=/usr/bin/xauth
Finally, there were still some files on my system from the old v6 of X11, so I moved them out of the way:
mv /usr/X11R6 /usr/X11R6_old
If you don't do this, apparently NX will get confused.