First all sorry top-posting...
Hmmm... I did that too.
NuttX also have support to dot-matrix displays, see this "mp3 player" running NuttX:
I'm not certain, but I don't think that this example is using any of the NuttX graphics facilities. I am not sure what he is doing, but the fonts don't look familiar (NuttX supports 17 different Helvetica and Times Roman fonts) and the drawing certainly does not come from Nuttx. I don't have any good demos of the graphics from NuttX but they are all rendered as "3-D" images. I've attached the output of the button array unit test to give you a better idea of what I mean.
(That attached PNG came from here: http://nuttx.svn.sourceforge.net/viewvc/nuttx/trunk/NxWidgets/UnitTests/CBut...)
This button array, by the way, can used with a touchscreen as an on-screen keyboard (with the output going to an edit box). "Widgets" like this have already been used to implement the complete GUI for a medical device.
Greg
