1. I'm trying to build my own addon, and this code should bring up a frame when enter the world

     <Ui xmlns="http://www.blizzard.com/wow/ui/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.blizzard.com/wow/ui/
     <Frame name="Newframe" parent="UIParent">
     <Size x="384" y="512"/>
                <Layer level="BACKGROUND">
                    <Texture setAllPoints="true">
                        <Color r="0" g="0" b="0" a="0"/>
     <Anchor point="CENTER" relativePoint="CENTER" relativeTo="UIParent"/>

    the .xml file are correctly load on the .toc file, and the .lua file is empty, but nothing appears

    An alpha of 0 is fully transparent. You won't be able to see that frame.