I have template called Gallery:
<sgallery width="320" height="240" showarrows="true" showcarousel="true" showinfopane="true" timed="true" delay="5000"> {{{1}}} </sgallery>
Ah, now I see what you are trying to do, and I can also replicate the problem; unfortunately, I don't know how to fix it. When the template is called, it should replace {{{1}}} with the argument, but it doesn't. It looks like the extension is being parsed before the argument is replaced.
Any developers have any ideas?
V/r,
Ryan Lane