[Xrystal]

Ah thats the old way .. hold on

Replace this block

<Backdrop bgFile="Interface\DialogFrame\UI-DialogBox-Background-Dark" edgeFile="Interface\DialogFrame\UI-DialogBox-Border" tile="true">
            <BackgroundInsets>
                <AbsInset left="11" right="12" top="12" bottom="11" />
            </BackgroundInsets>
            <TileSize>
                <AbsValue val="32" />
            </TileSize>
            <EdgeSize>
                <AbsValue val="32" />
            </EdgeSize>
            <Color r="0" g="0" b="0" />
        </Backdrop>

with

<KeyValues>
        <KeyValue key="backdropInfo" value="BACKDROP_DARK_DIALOG_32_32" type="global"/>
        <KeyValue key="backdropColor" value="BLACK" type="global"/>
        <KeyValue key="backdropBorderColor" value="WHITE" type="global"/>
    </KeyValues>

And if you want to look at alternative backdropInfo options. The top of this file has a bunch of pre-built ones.
https://www.townlong-yak.com/framexml/live/Backdrop.lua