Hi Tim,
Try this for the radio config file, I use it with a D4R-II:
<?xml version="1.0"?>
<!--
FrSky D8R 2 Plus receiver
Don't forget to jumper channels 3 & 4
CPPM on channel 1
-->
<!DOCTYPE radio SYSTEM "radio.dtd">
<radio name="FrSky D8R 2 Plus" data_min="990" data_max="2020" sync_min ="5000" sync_max ="27000" pulse_type="POSITIVE">
<channel ctl="1" function="YAW" min="991" neutral="1506" max="2014" average="0"/>
<channel ctl="2" function="PITCH" min="992" neutral="1504" max="2016" average="0"/>
<channel ctl="3" function="THROTTLE" min="1000" neutral="1000" max="2015" average="0"/>
<channel ctl="4" function="ROLL" min="995" neutral="1501" max="2014" average="0"/>
<channel ctl="5" function="MODE" min="992" neutral="1248" max="1761" average="1"/>
<channel ctl="6" function="GAIN1" min="1100" neutral="1520" max="1940" average="1"/>
<channel ctl="7" function="GAIN2" min="1100" neutral="1520" max="1940" average="1"/>
<channel ctl="8" function="GAIN3" min="1100" neutral="1520" max="1940" average="1"/>
</radio>