@brswattt some further comments. I would suggest you set the "queue management algorithm" to coddle in both the limiter (parent) and the child queue. You've set the scheduler but not the QMA.
Also, presumably you initiated the connection to steam. In which case I think you need to apply the rules on the LAN. I suspect that is the problem. If not, I would mark the rule to to be logged and then look at the firewall log and make sure your rule is triggering correctly. If not, work out why. You seem to be aware of the need to sometimes set quick actions on the floating rules to make the fire immediately but it could be something like that (though not from the looks of things).
As an aside, I would avoid using the floating rules and the WAN until you have this set-up right on the LAN itself. I say this because it is just easier and, as NAT is applied before the rules apply on the WAN, there can be problems writing rules that hit the packets intended. The workaround is tagging packets on the original interface before they hit the WAN then searching for the tagged packets. But the point is avoid applying stuff on the WAN and via floating rules until it is right on the interface rules.
