Watchguard edge VPN problem

I have a Firebox x550e at one server and an older Firebox III/700 at the corp office.  Each branch office has a Edge x10e-w.  I've had no problems setting up the VPNs between the servers and the branches until I got this last Edge firebox.  I'm pretty new to all this but I did notice that the firmware on this one is 8.6.1 whereas the past ones was 8.5.x.  I've tried all sorts of different settings, making sure they match on both ends exactly but still the VPN wont go active.  I called the ISP to make sure they weren't blocking any ports and they aren't.  I even went so far as to send the branch a DSL modem of the exact model as the other branches and it's in bridge mode as it is everywhere else and still no VPN.  I did pull the config file from an older router and loaded it into this newer one, could that be what's causing the problem, even though I'd manually checked all the setup and matched it with a working branch?  I've also tried another new edge to make sure something wasn't wrong with the firebox.  Everything else in the firebox seems to be working fine, they can access the internet and wireless and everything.  I noticed the newer firmware has a few more options, could it be that I need to setup a VPN or IPSEC policy for this one.  The older ones don't show a policy for them.