am I able to search the web interface with the users player ID? Ie. the one that starts with 'g:'?
You can search for the *Flox* player ID: that's the one that does *not* start with "g:", but is a random alphanumeric String created by Flox. That's the reason why I recommend the detour of the query that uses the *GameCenter* alias.
It seems to me you are thinking too complicated here. You already have everything in place: the player entities already contain the "alias". If you look into the web interface and just browse through the players, you will see that all of them include "alias" and "GID" (right?).
Now all you have to do is create that small utility program that makes a query using that "alias". That's the code I showed above! In the "onComplete" method, simply print out the player id (
trace("Player ID: " + players.id);). Then copy that value into the clipboard and paste it into the search field on the web interface. That's it!
[Don't forget to create the index in the web interface, too.]
In other words: your players are all there, but you need their *Flox* player ID to get to them in the web interface. So you use a utility program to get from the player alias to the Flox player ID. It has to be the alias, because that's what the users will be able to tell you (they don't know their GameCenter id).