Please note that the vim-lua-inspect plug-in requires my vim-misc plug-in which is separately distributed.
Unzip the most recent ZIP archives of the vim-lua-inspect and vim-misc plug-ins inside your Vim profile directory (usually this is
~/.vim on UNIX and
%USERPROFILE%\vimfiles on Windows), restart Vim and execute the command
:helptags ~/.vim/doc (use
:helptags ~\vimfiles\doc instead on Windows).