asterisk users - Mar 2004 - X-Lite on both sides of NAT with * behind the NAT

Hi,

I'm confused about a config we have going where there is

NAT router --> 192.168.1.101 linux+asterisk
PC         --  192.168.1.104 WinXP with X-Lite

At another location:

NAT Router --> PC X-Lite xxx.xxx.xxx.xxx

The remote works fine with *, can use the FXO line, can call FWD members 
thru *, can register with various services eveything seems to work fine.
The problem I have now is that I want the person behind the NAT router 
at the office to be able to call me and transfer calls and vice-versa.

Port 5060 and a bunch of ports starting at 10000 are forwarded to the * 
box. How can I configure the PC at 192.168.1.104 to be able to talk both 
to * and thru * AND be handed off to me? Is it even possible?

I tried setting the session port to 5063 and forwarded that to the PC at 
104 and when I called the office we "connected" but there was no
audio.

Can someone clear up the mystery of the RTP ports for me? My home X-Lite 
starts at 8000 and I have a large number of ports above 8000 forwarded.
I'm assuming the problem has to do with the RTP ports not being passed.

thx,

r