Manual Outbound NAT with 2 WANs using failover

[lieutdan13]

2.0.1-RELEASE (amd64)
em0 - LAN
rl1 - WAN1XO (Secondary ISP)
rl2 - WAN2TWC (Primary ISP)

Gateway Groups

| Group Name | Gateways | Priority |
| Failover | WAN1XOGW
WAN2TWCGW | Tier 2
Tier 1 |

Outbound NAT (Manual Outbound NAT enabled)
…Host-specific rules above the last...
Interface: WAN2TWC; Source: 192.168.1.0/24; Source Port: *; Destination: *; Destination Port: *; NAT Address: *; NAT Port: *; Static Port: NO;

Because I have a need for Manual Outbound NAT to force an outbound public IP AND implement failover for the rest of my machines inside the network, my question is:
How do I configure the Outbound NAT to use failover when a Interface is required for the rule?

[cmb]

NAT has nothing to do with where traffic goes, it only specifies how it's translated when it goes out the specified interface.

[lieutdan13]

@cmb:

NAT has nothing to do with where traffic goes, it only specifies how it's translated when it goes out the specified interface.

I understand this, but I'm telling you that with without an Outbound NAT rule assigned to the specific interface, outbound traffic does not work. If I disable (unplug) my primary Internet connection, the failover works properly, but I still have to manually change the Outbound NAT rule for "everything else" to use the secondary interface.

[cmb]

You never change outbound NAT. You have to have two outbound NAT rules, one for each WAN, if using manual outbound NAT.