Failover, static public IP, and virtual IPs.

[Marc05]

What I have:
Comcast Gateway (router IP 10.1.10.1 with a regular static public IP)
xDSL Gateway (dynamic public IP in 10.1/8 subnet)

The goals is:
pfSense 2.1.4-RELEASE (WAN1 public IP | WAN2 dhcp)
WAN1 as main, WAN2 as failover.

I thought I knew what I was doing, but after I added the static public IP under WAN1 interface, it gave an error when I tried to edit it under System>Routing. It said the gateway was not in the same subnet (I tried adding the public gateway). Essentially, the Comcast gateway would act as a bridge.

Also, on my current router, I have something called multi-homing which allows me to route traffic for two additional subnets (192.168.11.0/24 and 192.168.105.0/24). I'm guessing that this is called "Virtual IPs" in pfSense. If that is not the case, how would I set it up?

EDIT: Resetting the router to factory defaults and importing the settings afterwards allowed me to do what I wanted without an error. However, I'm still not positive if what I did was right or not.