Well, it happened again. This time, though, I think I know what caused it. I renamed the directory where my library resides and then in MJ I re-imported the tracks from the new directory and then updated the library to Remove files which do not exist. Now, all the Replay Gain info for the MPCs (over 1000) in my library is gone, however, the RG info for MP3, Vorbis and Monkey's was retained. It's only MPC that has a problem.
Rob
Listening to: 'E Mi Chanto' from 'Polyphonic Songs From The Southern Alps' by 'Corou De Berra' on Media Jukebox
Media Jukebox PLUS 8.0.393
Install Path: C:\Program Files\Media Jukebox\
CPU: Intel Pentium III 731 MHz MMX
Memory: Total - 261 MB, Free - 133 MB
Resource Info: System - 54 %, GDI - 79 %, User - 54 %
OS: Microsoft Windows 98 SE
Internet Explorer: 6.0.2800.1106
ComCtl32.dll: 5.50.4916.400
Shlwapi.dll: 6.00.2800.1106
Shell32.dll: 4.72.3812.600
wnaspi32.dll: 4.60 (1021) , ASPI for Win32 (95/NT) DLL, Copyright © 1989-1999 Adaptec, Inc.
Aspi32.sys: N/A