I had the correct operating system and MP version selected for the download. The system information is below. Thank you very much for taking a look at this; I'm not usually such a problem-child.
Media Center Registered 11.1.111 -- C:\Program Files\J River\Media Center 11\
Microsoft Windows XP Workstation 5.1 Service Pack 2 (Build 2600)
Intel Pentium 4 2971 MHz MMX / Memory: Total - 1571 MB, Free - 1147 MB
Internet Explorer: 6.0.2900.2180 / ComCtl32.dll: 5.82.2900 / Shlwapi.dll: 6.0.2900 / Shell32.dll: 6.0.2900 / wnaspi32.dll: N/A
Ripping / Drive D: Mode:Normal Type:Auto Speed:Max
Drive E: Mode:Normal Type:Auto Speed:Max
Digital playback: Yes / Use YADB: Yes / Get cover art: No / Calc replay gain: Yes / Copy volume: 32767
Eject after ripping: Yes / Play sound after ripping: No
Burning / Drive E: _NEC DVD+RW ND-2100AD Addr: 0:1:0 Speed:32 MaxSpeed:32 BurnProof:Yes
Test mode: No / Eject after writing: Yes / Direct decoding: Yes / Write CD-Text: Yes
Use playback settings: No /