The one issue that I see is that this is going to be one of those "PITA" things that will dissuade people from even using it. To counter our laziness, I would do the following:
During installation / configuration of the initial Rift setup, add the warning there, with the line, "By continuing installation, the end user acknowledges that they read the warnings" or something. Then, don't display it again.
Let the developers add in their specific warnings, etc.. for when their game launches. This should be a "best practices" guideline. Oculus could distribute a generic warning label, but allow the developers to customize it if they so wish.
Current WIPs using Unreal Engine 4:Agrona - Tales of an Era: Medieval Fantasy MORPG