the 4wd route is not a mixed use trail, the only mixed use sections of trail are there so that atv riders (and the like) can connect to the various loops they have (although not all will connect). most of these will be on sections of main roads such as the pipeline (old 97, new 09).
the ohv trails are not for licensed vehicles, those are to be for atv or ohm rigs and is fee based. no licensed trail will have 4 numbers like that without a dash somewhere mixed in.
that link above shows the atv/ohm routes. OHV in the federal forests means unlicensed vehicles.
the different color dots i used was simply to indicate 3 main areas: North, South West and South East however it has no further distinction, i was merely attempting to "mix it up" on the map. if you had a really large group you could split into 3 smaller groups and not get bottled up on the trail by choosing different routes. the dots themselves indicate a gps coordinate/waypoint.