Background texture does not tile. Can you help me?

[griffonmtl]

Hello everyone,

I've started to learn how to do some AddOn (mostly for fun) and i have some problem with a background of a Frame. While I can put the image I want as background, it does not tile correctly. It tiles horizontally but not vertically (as you can see on the attached picture). I was wondering if someone can advise me on what is the problem with my code:

<Ui xmlns="http://www.blizzard.com/wow/ui/"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
	<Script>
		print("ALLOOOOOO")
	</Script>
	<Frame name="TestUI" hidden="false">
		<Anchors>
			<Anchor point="Center" />
		</Anchors>
		<Size>
			<AbsDimension x="200" y="200" />
		</Size>
		<Backdrop bgFile="Interface\AddOns\HelloWorld\bg001.tga" tile="true"
			edgeFile="Interface\DialogFrame\UI-DialogBox-Border">
			<TileSize>
				<AbsValue val="32" />
			</TileSize>
			<EdgeSize>
				<AbsValue val="32" />
			</EdgeSize>
			<BackgroundInsets>
				<AbsInset left="11" right="12" top="12" bottom="11" />
			</BackgroundInsets>
		</Backdrop>
	</Frame>
 </Ui>

I did not provide the lua code, since there is nothing on it yet. Also, the file is power of 2 tga.

In advance... thanks