Rendering SVG images everywhere with Modernizr, CanVG and ExCanvas

Question

The website I'm making (here) has all its images as SVG. But since SVGs aren't compatible everywhere (notably IE <9 and Android browser on versions 2.x), I needed to find a workaround. That couldn't be SVGweb, since that uses Flash, and Flash doesn't work on mobile devices.

So I thought I had found a working solution.

compatibility.js:

$(document).ready(function() {  
    yepnope({
        test: Modernizr.svg,
        nope: ['extensions/canvg/rgbcolor.js','extensions/canvg/canvg.js'],
        complete: function(url,result,key) {
            if(!Modernizr.svg) {
                yepnope({
                    test: Modernizr.canvas,
                    nope: 'extensions/excanvas.compiled.js',
                    complete: function() {
                        canvg();
                    }
                });
            }
        }
    });
});

But this seems to have no effect whatsoever, and since there are no errors and I can't find any logical errors, I'm stumped. Here is my tag, in case I messed up the load order of something.

<script type="text/javascript" src="extensions/less-1.3.3.min.js"></script>
<script type="text/javascript" src="extensions/jquery-1.9.1.min.js"></script>
<!--[if (gte IE 6)&(lte IE 8)]>
    IE!!!!
    <script type="text/javascript" src="extensions/selectivizr-min.js"></script>
<![endif]-->
<script type="text/javascript" src="extensions/modernizr-2.6.2.min.js"></script>
<script type="text/javascript" src="compatibility.js"></script>
<script type="text/javascript" src="scripts.js"></script>
<title>Myriam coiffure et esthétique</title>

Also, this isn't the main question, but if you happen to figure out why Selectivizr isn't working, please do tell.