aagh that wasnt supposed to post - I fat fingered it. Do I need the resource manager for just a simple 20-30 person gaming community who uses the forum to keep track of each other across different games and occasionally share you-tube videos?
if I decide later that I want it, is it a pain in the rear to add it? Fairly inexperienced here but I have maintained two different phpbb forums years ago.
If you do not plan to utilize it for resources, articles, etc. it may not be necessary for you. If you purchase your license and decide you need the resource manager at a later date, it is always an option to purchase it when you need it.
If you do not purchase it, you will still be able to attach files to posts or style threads to look like articles, but yes, you will not find a "resource" section within your ACP after unless you purchase and install the add-on.
If you would like to evaluate the features available, you can request a demo of the software here: http://xenforo.com/demo/