Microloader looking for "/.js" after building app

I'm using the following versions:

Sencha Architect

After building my app (with "production") and trying to load it in my browser, it's trying to find a "/.js" file (extension, but no name!) which obviously isn't going to work. I've checked my app.json and all files exist and have both filename and extension.

What should I look for to find out why this is happening?

Here's the output from Chrome (v. 40, Windows) Developer Tools:

IssuesLog built app broken.PNG

Thanks.

Microloader looking for "/.js" after building app