"Custom-Backdrops"? - Need Help

[Segore]

Hello,

atm I'am creating a little addon that should show a Frame on READY_CHECK.
That part of my little addon is working as expected, but there is one part which is not working - here is the code of my Frame:

BFC_Frame = CreateFrame("Frame", "BFC_Frame", UIParent)
BFC_Frame:EnableMouse(true)
BFC_Frame:SetMovable(true)
BFC_Frame:SetUserPlaced(true)
BFC_Frame:RegisterForDrag("LeftButton")
BFC_Frame:SetScript("OnDragStart", function() this:StartMoving() end)
BFC_Frame:SetScript("OnDragStop", function() this:StopMovingOrSizing() end)
BFC_Frame:SetWidth(112)
BFC_Frame:SetHeight(56)
BFC_Frame:SetPoint("CENTER", 0, 0)

BFC_Frame:SetBackdrop({
  bgFile="Interface\\DialogFrame\\UI-DialogBox-Background", 
  edgeFile="Interface\\DialogFrame\\UI-DialogBox-Border", 
  tile=1, tileSize=10, edgeSize=10, 
  insets={left=3, right=3, top=3, bottom=3}
});


BFC_Frame:Hide()

-- Frames für Buff/Flask-Icon
BFC_B_Frame = CreateFrame("Frame", "BFC_Frame", BFC_Frame)
BFC_B_Frame:SetWidth(56)
BFC_B_Frame:SetHeight(56)
BFC_B_Frame:SetPoint("LEFT", 0, 0)
BFC_B_Frame:Hide()
BFC_B_Frame:SetBackdrop({
bgFile="Interface\\AddOns\\BuffoodFlaskCheck\\UI-BuffoodFlaskCheck-Backdrop-Food",
edgeFile="Interface\\DialogFrame\\UI-DialogBox-Border",
tile=0, tileSize=10, edgeSize=10,
insets={left=3, right=3, top=3, bottom=3}
});

It seems that the Frames are created correctly, but the backdrop of the BFC_B_Frame Frame doesn't show the bgFile as you can see here:
http://img341.imageshack.us/img341/5...odflaskche.png

The file is saved in the tga-Format.

Any ideas why it is not working?