Refresh and stylize a Tree View - Perspective

hello !
I have two little problems, maybe you’ll know the solution…

first off all I populate my tree view like this :

Problem 1 :
i want to refresh my tree with a message handler


I don’t have any error so i guess its works but i don’t have any refresh.
For example i create a new tag but nothing or i delete a tag but it still here. (you can see it in the first screen with the “new instance”)
And, if i manually go in my items binding and i apply again my configure transform(s) script, the tree is refresh

Problem 2 :
i want to have different color for each tag in my tree view which will depend on whether or not I’m logged in.

like the table at the left, but in the tree:
but i don’t find a way to do it

thanks in advance.