I played around with it a little and this is what I found.
Just clicking on the green arrow to disable the rules doesn't work. You have to edit the rule, check disable, save, apply changes, edit rule, uncheck disable, save, apply changes and then the queue is applied correctly.
Interfaced don't need to be applied. The point of the floating rules was that the interface didn't need to be selected so you can classify traffic with less work.
I think what adding a specific interface did, which disabling and enabling does also, is force the rule to be rebuilt.
My rule went from this.
pass out proto tcp from any to any port = 3389 label "USER_RULE: m_Other MSRDP outbound"
to this.
pass out proto tcp from any to any port = 3389 keep state queue (qOthersHigh,qACK) label "USER_RULE: m_Other MSRDP outbound"
Josh