For debugging the WDC you can use the Tableau Simulator which is outlined in the following section of GitHub.
NPM also has there own section for Tableau on their site that might contain some additional information.
Finally, if you could provide some more information as to what is occurring during the failure, error messages, unexpected behavior, etc... There is a potential someone from the Tableau Community could provide some more information on the unexpected behavior.
Hope this helps!
I haven't even gotten to the stage of WDC creation. Specifically, the issue was that 'npm start' had various reasons it refused to load, but I didn't figure I'd get much help on Node/NPM issues here. While I'd be happy to get into details and troubleshoot with you or someone else in this community, my question was looking for alternatives to that process. That second link sounds promising though, thank you!
I also found some additional information on NPM and its error messages.
Was the second link I provided contain the necessary information to resolve the issue?
Unfortunately not, but it gave me more resources to research/ask for help about. And yes, I've been through the NPM website and troubleshot all I could, so I've used the document you linked today.