Okay let me expliain you a bit more about this
Collin can correct me later if im worng but thats how i make it work
Let say on the remote site
Let say you got 2 VLANs that goes to the Bridged AP
let say vlan 5 is untagged and vlan 10 is tagged
Scenario 1 Let say vlan 5 is the one that you want users use as the vlan for the wireless okay?
Then on the virtual AP, you can put vlan 1 as is the untagged so it doest matter...
This is true if on under ap system profile, the native id of the vlan is 1 and if that number matches the one on the VAP the traffic will be send untagged on that port, since the paramther by default is always 1 you also set the vlan on the vap on 1 then the trafffic will send untagged on that port.
Scenario 2
But let say you want that ppl use the tagged vlan on the remote site which is 10
I know you dont have created that vlan on your wireless contorller because that vlan does not exist on the central site...
It doesnt matter is does not exist you have to put in the VAP(Virtual AP) vlan 10(it will accept it even if it does not exist) so just put it.
Remenber the Configuration you put in there is downloaded to the Brdiged AP and even if its not tunned back well the ap will get that info which it needed.
The scenario 1 is convenient if you got many small site in which you will bridge the AP but also take in mind it will be convenient just having the AP and the wireless clients on that vlan you dont want to have wired and wireless client on the same vlan... also you can with the penf block traffic of the users so they wont see the Wireless controller if you want.
Now why its convenient? well its because it will make you configure less...rather that if you got a different vlan for each site. You will just configure every VAP with vlan 1... and thats it... and yeah you on the remote site might have vlan 20, 30, 40 all untagged on the port of the AP but since they are untagged and you will use that vlan then i doesnt matter you still just have to put vlan 1 which is hte default value of the VAP so you configure less..
I hope that helps you
Now this is a question i ask to collin just to be sure 
If the vlan 10 exist back in my wireless controller and is used for another AP let say vlan 10 exist in the wirelss controller for let say a VAP is tunneled back but i also got a vlan 10 on the remote site, i can safety put vlan 10 as the info will be downloaded to the AP and if if not bridged back it will just tell theAP to use the local vlan 10 and if it tunneled back it will use the vlan 10 on the controller rigth?