5.2. OK, so how do I protect a directory as read only?

Same as above, only specify /some/directory
bash# lidsconf -A -o /some/directory	 -j READONLY
When the object is a directory, LIDS protects the directory itself, and it recursively protects everything underneath it within the same file system. (e.g. LIDS ACLs do not cross file system boundaries!) This is very important to remember so you don't accidentally leave part of your system unprotected.

A directory that you may want to protect as read only is the /etc directory.
bash# lidsconf -A -o /etc -j READONLY