OK, I found where I was going wrong. I re-read the page more carefully, and realized I had to go under "Advanced > Configuration", so I can now add device codes.
One clarification, however. the instructions at
http://wiki.linuxmce.org/index.php/Add_support_for_new_remote_controls say the following:
5. Capture the key codes: In a terminal window, enter the command tail -f /var/log/pluto/XX_USB_UIRT_0038.log where XX is the device number you found in the previous step. Press a button on the remote control twice. You should see something like this:
05 05/16/08 19:29:18.757 Cannot find anything for IR 1500003E3CFC <0x40800950>
05 05/16/08 19:29:19.021 Cannot find anything for IR 1700009E0FC0 <0x40800950>
The numbers 1500003E3CFC and 1700009E0FC0 are the key codes for that button. If the two numbers are the same, then there is only one key code for that button. In a text editor, format the button names and key codes in the same format as this.
6. Add the Configuration (string): In the Device Data box select Configuration. Paste the key codes you created in the last step into the Default Value field. Click the Use Master Device List Defaults box.
My device ID is 46, and is a "Generic Serial Device". I did the tail on "/var/log/pluto/46_Generic_Serial_Device.log" and pressed a couple of the keys twice, but nothing showed up. Can I just use the codes in the lircd.conf file, or does pluto use a different format? the codes in my file look like this:
1 0x1781
2 0x1782
3 0x1783
4 0x1784
5 0x1785
6 0x1786
7 0x1787
8 0x1788
9 0x1789
0 0x1780
The output from irw looks like this:
0000000000001783 00 3 hauppauge.pvr500
0000000000001783 01 3 hauppauge.pvr500
0000000000001783 02 3 hauppauge.pvr500
0000000000001782 00 2 hauppauge.pvr500
0000000000001782 01 2 hauppauge.pvr500
0000000000001782 02 2 hauppauge.pvr500
0000000000001795 00 Down hauppauge.pvr500
0000000000001795 01 Down hauppauge.pvr500
0000000000001795 02 Down hauppauge.pvr500
0000000000001796 00 Left hauppauge.pvr500
0000000000001796 01 Left hauppauge.pvr500
0000000000001796 02 Left hauppauge.pvr500
0000000000001797 00 Right hauppauge.pvr500
0000000000001797 01 Right hauppauge.pvr500
0000000000001797 02 Right hauppauge.pvr500
0000000000001795 00 Down hauppauge.pvr500
0000000000001795 01 Down hauppauge.pvr500
0000000000001795 02 Down hauppauge.pvr500
0000000000001797 00 Right hauppauge.pvr500
0000000000001797 01 Right hauppauge.pvr500
0000000000001797 02 Right hauppauge.pvr500
(the same codes, but with just a bunch of "0s" in front)
Thanks again for your help!
-SilkBC