Hi
Could you publish more information about your environment, especial about the how do you deploy your ocs edge server.
And how do you configure the interface of the edge server.
Per your description, your issue are
1. AV conferencing between internal & external users does not work,
2. external user to external user (p-to-p) in different location/routers are not working
The issue is usually caused by a uncorrectly confiuration of the edge server, wrong confiuration on the firewall, worng topology between perimeter network and the Internet
, and have not routable ip for those.
Did you deploy your edge server according to below link
http://technet.microsoft.com/en-us/library/bb803625.aspx Especial configure the firewalls you can refer to below link
http://technet.microsoft.com/en-us/library/bb803617.aspxyou'll need to configure your external perimeter firewall to route a public IP address to the Edge server and bind that address directly to the external interface. The Access Edge and Web Conferencing services can use NAT'd private IP addresses in any subnet, but not the A/V service. The AV Edge Server must have addresses that are directly routable at the IP layer and so cannot be run behind a NAT.
You canDesigning Your Perimeter Network for Office Communications Server 2007 from below link
http://www.microsoft.com/downloads/details.aspx?familyid=959cb709-d81e-4dde-821f-0411dfcfc073&displaylang=enIf i misunderstand your issue, please tell me.
Regards!