OK, let me simplify my question. I have a music library on my desktop HD that contains 4419 files and is 136 GB in size. How do I make a copy of that library and all associated files (music, meta, tags, etc) to put on my laptop in an externally mounted HD?
This may not be exact, but it's a good outline of the steps necessary:
1. Make a Library backup of your current MC Library. This exports all of the metadata to a zip file. It does NOTHING with the music files themselves. File > Library > Backup Library .
2. Copy your music folder (hopefully it's just one parent folder) to your external hard drive. It's important to not change the directory structure here. Just do a 1 for 1 copy.
3. Copy the Library Backup file over to the other computer (laptop), and attach the external drive.
4. Import your library backup into a fresh library on the new computer in MC. File > Library > Restore Library. You'll need to point the restore process to the Library Backup zip file that you copied over in step #3 above.
5. Now you should see all of your songs, but they will all have red minus signs (-) next to them because MC can't find them in their original paths from your source computer.
6. Fix those paths with the Rename, Move, and Copy files tool. This requires a bit of explanation:
If, for example, your files on the source computer were in: /Volumes/MacHD/Users/LDF/Music/ ...and they are now on your new computer at: /Volumes/ExtDrive/Music/ ... then you need to tell MC to change the first part of the file path for all files it it's library. You'll want to replace /Volumes/MacHD/Users/LDF/ with /Volumes/ExtDrive/ .
The Rename, Move, and Copy files tool can do this in what is called Update Only mode. In this mode it does not try to move or copy files. It only changes their location inside MC's database. You'll want to use another mode of the RM&C tool in combination with Update mode. It's called the Find & Replace template. That template is at the bottom of the tool. It allows you to substitute part of the file name by doing a Find and Replace. Here's the wiki entry on RM&C:
https://wiki.jriver.com/index.php/Rename,_Move,_and_Copy_FilesBe sure to read the section on the Find & Replace template. There are some examples there that should help.
I hope this gets you started in the right direction. Good luck!
Brian.