I want show a bitmap on EXPLORERBAR NOT ON A SINGLE PANEL

LOCAL oBrush := TBrush():New("NULL",,,)
@ 420, 15 BITMAP oApp:oLogoBmp FILENAME ".\bitmaps\fivetech.BMP" NOBORDER PIXEL OF oApp():oExBar
oApp:nClrPane := oApp():nClrPane //GetSysColor(3)
oApp:lTransparent := .t.
oApp:oBrush := oBrush
it show the bitmap but not is transparent, why ?

LOCAL oBrush := TBrush():New("NULL",,,)
@ 420, 15 BITMAP oApp:oLogoBmp FILENAME ".\bitmaps\fivetech.BMP" NOBORDER PIXEL OF oApp():oExBar
oApp:nClrPane := oApp():nClrPane //GetSysColor(3)
oApp:lTransparent := .t.
oApp:oBrush := oBrush
it show the bitmap but not is transparent, why ?
FWH .. BC582.. xharbour