Hi Frank,
don’t know where you got that idea, but Procoding is not a HTML/CSS editor, but a JavaScript Editor.
While you can add HTML and CSS as resources (currently not editable on iOS, a feature that is planned and will come eventually), the main focus of Procoding is to code small JavaScript based sketches.
Please have a look at the provided demos, (automatically installed on iOS, right below the File > Open menu on OS X). Some of them contain additional resources, some of them don’t.
I’m not sure if you’re talking about the OS X or the iOS version,
Procoding Mobile also contains a help section that explains the features of the templates and has many links to useful sites and online tutorials that should help you to get started.
Weather or not to use the Canvas or non-Canvas template… I can’t say, depends on what you want to do ;-)
Best,
Michael