Rendering can be based on attribute fields containing non-numeric information as well. For instance:

RENDER=( Sex = 'MALE' )
or
RENDER = ( Street Type = 'Main' )
RENDER = ( Street Type = 'Secondary' )

Be sure to use  ' '  marks and not  " "  to connote a non-numeric item.

Or you might find it easier to use the desktop TatukGIS Viewer (free product) or Editor or to set up the rendering and save to a TatukGIS project file for use with the DK.