Problem to Display PNG.

Hellu everybody.

My name is Sebastien, and I'm trying to create my first custom watchface, using API 4.2.0.

I wish to display a png accorded to the battery % (in color, so no custom font,, am I right?).

I identified images in drawables.xml this way :

    <bitmap id="Orb100" filename="Images/Orb100.png" />
    <bitmap id="Orb090" filename="Images/Orb090.png" />
    <bitmap id="Orb090" filename="Images/Orb090.png" />
    <bitmap id="Orb080" filename="Images/Orb080.png" />
    <bitmap id="Orb070" filename="Images/Orb070.png" />
    <bitmap id="Orb060" filename="Images/Orb060.png" />
    <bitmap id="Orb050" filename="Images/Orb050.png" />
    <bitmap id="Orb040" filename="Images/Orb040.png" />
    <bitmap id="Orb030" filename="Images/Orb030.png" />
    <bitmap id="Orb020" filename="Images/Orb020.png" />
    <bitmap id="Orb010" filename="Images/Orb010.png" />
    <bitmap id="Orb000" filename="Images/Orb000.png" />
 
In WatchFaceview.mc, I set the right file this way : 
        var batIcon=WatchUi.loadResource(Rez.Drawables.Orb100);
            if (battery<95) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb090);}
                else if (battery<85) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb080);}
                    else if (battery<75) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb070);}
                        else if (battery<65) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb060);}
                            else if (battery<55) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb050);}
                                else if (battery<45) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb040);}
                                    else if (battery<35) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb030);}
                                        else if (battery<25) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb020);}
                                                else if (battery<15) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb010);}
                                                    else if (battery<5) {batIcon=WatchUi.loadResource(Rez.Drawables.Orb000);}
Now I wish to display the PNG in layout.xml, like my text datas, but however I try (and I tried...), I get some error message.
Anybody has the solution ?
Many thanks in advance!