While we're waiting for further from the NTSB...
On any computing machine,"36" (inner scale) against the groundspeed (outer), find distance (eg., FAF to MAP or threshold) on the outer, read number of seconds on the inner. 36:140 = 90:3.5...thirty-six against 140kts is 90 seconds for three-and-half nautical miles.
For rough rate of descent, (point to point, say, FAF altitude to MDA or MAP altitude), put that number of seconds, (here, '90'), against the height to lose, (say, 1100') and read the rate of descent against the "60" index, (760fpm).
Obviously as with every indication and calculation one has to do a reasonableness check!, and some adjustments and accomodations have to be made, (the 50' thing, which FAF alt & MDA to use, etc), but the method can produce the same numbers as on the Jepp charts.
On the trig side of the CR machine, the "TAS" index can be placed against the groundspeed and one can read the rate of descent for a particular descent path...TAS index against "140", read the rate of descent for a "3deg" descent path against '3' on the "SIN" (inner) scale, which is 760fpm, (the black part of the scale reads "COS"). The SIN scale can also be used to read crosswind component...TAS at the windspeed, xwind component at the offset degrees...30kts, 25deg diff between heading and wind direction is 15kt xwind...etc.
This will all be old-hat to many, but not to everyone. It is sufficiently precise to do the job, (and did until microprocessors came along a few years ago...) and can even be part of the non-precision briefing just as a check on things.