This should be fairly straightforward. If your application already has an application.cfm (and it should) you can just take the code from AccessMonger's Application.cfm and work it into your own.

You can drop the files in with the rest of your web documents, or put them into their own folder and refer to them via relative url links (which will also make it much easier to protect files in more than one directory).

If you don't need multilevel access, just set every user's access level to 1, and do the same for every page's PageLevel setting.