Widget working locally but not in the cloud

I wrote a small Markdown to HTML converter widget, based on the Showdown converter. Magically, it works locally, but not in the cloud. I get the error "showdown.Converter is not a constructor".

My assumption is that it cannot find my lib file to which I refer in the require:

require([ blablabla "Showdown/lib/showdown" ], function(blablabla, showdown) {

Do you have any idea what can cause this? Is the relative path to a lib file read differently in the cloud? Otherwise, would there be a good practice to refer to the CDN-hosted lib file instead of having it in the widget?

The source code can be found here: GitHub