For resources I just copy them over, so everything under $package/resources comes on the NGINX server under /web/resources/$package and NGINX is configured to get it from there.
For static content that resides in /www, you can mount those directories via NFS and have NGINX pull it from there, or, alternatively, and much better if you do not change static files often, run RSYNC on a regular basis.
I would not recommend setting up a local NGINX for the static files, as you loose the benefit of not having to pull the files from the server running AOLserver.
Also be aware that a good practice for me was to use NGINX for SSL and not AOLserver (reduces load on the NSD process).
And you can do reverse proxy based on URL, which means you can run part of the URL (e.g. like /image, /file, /shared/portrait-bits) from an AOLserver just used for CR File distribution.