I've experienced the same error upon trying to install the plugin for the Nomad Jukebox. This is a re-install of Jukebox on a pristine system (I just did a clean install of Win98 moments ago). This plugin worked earlier on this same PC before my Win98 reinstall.
Here is the error:
Failed to install package.
More Info: Failed to register object.
C:\Program File\MediaJukebox\Plugins\hh_nomadjukebox.dll
Here is the system info:
Media Jukebox PLUS 8.0.336
Install Path: C:\Program Files\Media Jukebox\
CPU: Intel Celeron 397 MHz MMX
Memory: Total - 130 MB, Free - 69 MB
OS: Microsoft Windows 98
Internet Explorer: 4.72.3110.0
ComCtl32.dll: 4.72.3110.1
Shlwapi.dll: 4.72.3110.0
Shell32.dll: 4.72.3110.6
wnaspi32.dll: 2, 0, 0, 0 , ASPI for WIN32 DLL, Copyright © Adaptec 1995
Aspi32.sys: N/A