While in the root account, I made some menu editor entries, and then copied the relevant file or folder (I forget which it was) in /root/config to the corresponding folder in /home/josh, thinking the entries would appear in the user account. Why didn't they? Do I need to do something else?

I'm not sure that /root/config is all you needed to copy. For me, anything I add to my Kmenu is stored in ~/.kde/share/applnk or ~/.kde/share/apps.

Also, if you copy from /root to your ~ you likely need to chown the files to belong to the target user. If they still belong to root you may not be able to read them, or may be able to read but not modify.

EDIT: I think applnk will be what you want. But you probably don't want to copy the whole applnk directory unless you know you want the entire menu to be copied. Instead browse through it and pick out the .desktop files you want and copy them. Then chown the applnk directory

Actually, the applnk directory is deprecated. Has been for a while. KDE now adheres to the FreeDesktop.org menu standard, which puts application shortcuts in the ~/.local/share/applications/ directory. That's where new shortcuts are going to be created.

I guess it's been a while since I've had a reason to know where they're stored.

Thank you, AdaHacker, for pointing me to .local and the FreeDesktop menu standard. Exploring that led me to some *much* needed pruning of my .desktop files and the kickerrc file.