Re: xslt component

            <xsl:template name="getsvg">
                <xsl:param name="data"/>
                <xsl:value-of select="string(convert:getSVG($data))"/>
             </xsl:template>

However, this approach does not work and I am not sure what went wrong!

I'm not sure either, but I guess you run your XSLT porcessor
SAX-pipelined to the FO processor, which gets a string rather
than a parsed XML tree for the SVG.
Try to run the XSLT standalone, save the result to a file, and
check whether the resulting file can be processed by your FO
processor. This won't help you much for solving your original
problem directly. There are, however, several approaches to solve
your original problem. I'd need some more details on how you are
running your software for this: does it run batch/CLI or embedded,
in case of the latter: which framework, can you use an URL to
acess the SVG data, can you plug a custom URIResolver into your
XSLT processor etc.