So far I have the registrations working somewhat and the registrations are visible in the Kamailio locations table but I also Freeswitch also needs to have access to these registrations as well so that we have access to the functionality within FusionPBX.

Here are the relevant bits of my script with the real public IPs substituted:

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# *** Value defines - IDs used later in config
#!ifdef WITH_PGSQL
#!define DBURL "postgres://kamailio:kamailiorw@localhost/kamailio"
#!endif
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#!ifdef WITH_FREESWITCH
#!define DBFSURL "postgres://fusionpbx:fusionpbx@1.2.3.4:5432/fusionpbx"
#!endif
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#!ifdef WITH_FREESWITCH
freeswitch.bindip = "1.2.3.4" desc "FreeSWITCH IP Address"
freeswitch.bindport = "5060" desc "FreeSWITCH Port"
#
kamailio.bindip = "2.2.2.2" desc "Kamailio IP Address"
kamailio.bindport = "5065" desc "Kamailio Port"
#!endif
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#!ifdef WITH_POSTGRES
loadmodule "db_postgres.so"
#!endif
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.
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# ----- usrloc params -----
/* enable DB persistency for location entries */
#!ifdef WITH_USRLOCDB  
modparam("usrloc", "db_url", "postgres://kamailio:kamailiorw@localhost/kamailio")
modparam("usrloc", "db_mode", 2)
modparam("usrloc", "use_domain", MULTIDOMAIN)
#!endif

  
# ----- auth_db params -----
#!ifdef WITH_AUTH
modparam("auth_db", "calculate_ha1", yes)
modparam("auth_db", "load_credentials", "")

#!ifdef WITH_FREESWITCH
modparam("auth_db", "user_column", "extension") 
modparam("auth_db", "password_column", "password")
modparam("auth_db", "domain_column", "user_context")
modparam("auth_db", "db_url", DBFSURL)
modparam("auth_db", "version_table", 0)
modparam("auth_db", "use_domain", MULTIDOMAIN)
#!else
modparam("auth_db", "db_url", DBURL)
modparam("auth_db", "password_column", "password")
modparam("auth_db", "use_domain", MULTIDOMAIN)  
#!endif
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# authentication
        route(AUTH);

        # record routing for dialog forming requests (in case they are routed)
        # - remove preloaded route headers
        remove_hf("Route");
        if (is_method("INVITE|SUBSCRIBE"))
                record_route_preset("2.2.2.2");

        # account only INVITEs
        if (is_method("INVITE"))
        {
                setflag(FLT_ACC); # do accounting
        }

        # dispatch requests to foreign domains
        route(SIPOUT);

        # handle presence related requests
        route(PRESENCE);

        # handle registrations
        route(REGISTRAR);

        if ($rU==$null)
        {
                # request with no Username in RURI
                sl_send_reply("484","Address Incomplete");
                exit;
        }
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.
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# Authentication route
route[AUTH] {
#!ifdef WITH_AUTH

#!ifdef WITH_FREESWITCH
        # do not auth traffic from FreeSWITCH - trusted!
        if(route(FROMFREESWITCH))
                return;
#!endif 

#!ifdef WITH_IPAUTH
        if((!is_method("REGISTER")) && allow_source_address())
        {
                # source IP allowed
                return;
        }
#!endif
       
        if (is_method("REGISTER") || from_uri==myself)
        {
                # authenticate requests
#!ifdef WITH_FREESWITCH
                if (!auth_check("$fd", "v_extensions", "1")) {
#!else
                if (!auth_check("$fd", "subscriber", "1")) {
#!endif
                        auth_challenge("$fd", "0");
                        exit;
                }
                # user authenticated - remove auth header
                if(!is_method("REGISTER|PUBLISH"))
                        consume_credentials();
        }
        # if caller is not local subscriber, then check if it calls
        # a local destination, otherwise deny, not an open relay here
        if (from_uri!=myself && uri!=myself)
        {
                sl_send_reply("403","Not relaying");
                exit;
        }

#!endif
        return;
}
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# Routing to foreign domains
route[SIPOUT] {
        if (!uri==myself)
        {
                append_hf("P-hint: outbound\r\n");
                route(RELAY);
        }
}
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.
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# Handle SIP registrations
route[REGISTRAR] {
        if (is_method("REGISTER"))
        {
                if(isflagset(FLT_NATS))
                {
                        setbflag(FLB_NATB);
                        # uncomment next line to do SIP NAT pinging
                        setbflag(FLB_NATSIPPING);
                }
                # without param, here would allows multiple contacts, with 0x04 param, last register wins (fifo)
                #if (!save("location"))
                if (!save("location", "0x04"))
                        sl_reply_error();
       
#!ifdef WITH_FREESWITCH
                route(REGFWD);
#!endif

                exit;
        }
}
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.
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#######

I hope I haven't missed anything important.

With my current config I am able to dial feature code in FusionPBX and also make outbound calls but not able to dial between extensions because as far as Freeswitch is concerned the extensions are not registered.

Any assistance would be greatly appreciated.

Thanks

Errol