I just had a look at :help usr_90.txt about installing Vim. I have
a few suggestions.
1. Add a help tag, so :help install takes you to the top of the file.
2. Add a brief section at the beginning, mentioning that you need the
runtime files and suggesting that new users start with vimrc_example.vim
. Well, maybe the first part will not help: chicken-and-egg problem!
The second part might help: there have been several questions lately
like "why don't plugins work?" where the answer has been to :set nocp
and :filetype plugin on .