WAN2 was the one that went down.  I know it's a little weird, but I have WAN as my default gateway, yet WAN2 is the one where most traffic goes out, due to the weight & tier settings in the Gateway group below.  That aspect of it is working the way I want/expect it to.
Here's my settings:
WAN connection:				Triple bonded T1s		- 4.5Mbps up & down
WAN2 connection:			Business class Cable modem	- 50Mbps down/5Mbps up
WAN Gateway Settings:
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Address Family				IPv4
Gateway IP address			208.x.x.169
Default Gateway				Checked
Disable Gateway Monitoring		Not Checked
Monitor IP	 			
Weight					1
WAN2 Gateway Settings:
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Address Family				IPv4
Gateway IP address			71.x.x.17
Default Gateway				Not Checked
Disable Gateway Monitoring		Not Checked
Monitor IP	 			8.8.8.8
Weight					5
Gateway Group MultiWANFailover Settings:
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Gateway Priority			WANGW		Tier 2		wan_vip3 - 208.x.x.170
					WAN2GW		Tier 1		opt1_vip4 - 71.x.x.18
Trigger Level				Member Down
As far as floating WAN rules, I'm not sure what you mean, all that's in my floating firewall rules is autogenerated rules for my VOIP & P2P queues…  I haven't made any changes to my firewall rules in some time, and it used to work fine.  Do you want a complete posting of my firewall rules?