I just used the 120 ohm resistor across the 485 +/- lines and it worked fine. The CD that comes with the U485 adapter has a document that confuses the issue. I think shipping a TRI doument on the CD that outlines 485 connections and termanation issues would make the product even better.
Nano 10 is a great product ! I have used ADC inputs, PWM outputs to direct drive 2 DC motors in seperate PID loops, the devlopment was quick and the results excellent.
Also for applications that require absolute rotary feedback with long life this sensor is helpful. It interfaces directly with TRI ADC inputs and supply voltages.
http://sensing.honeywell.com/index.cfm/ci_id/140301/la_id/1/pr_id/128790.htm