I will start by saying that I'm fairly new to ESRI Story Maps. My organization has an enterprise license running Portal for ArcGIS as well as an ArcGIS Online account for simple app development. We don't utilize Web AppBuilder for Developer's addition, because we utilize Geocortex for our more heavy app dev.
That being said, there are those in the organization that love the interface of Story Map Journals, however part of the functionality that does not come out of the box, is the ability to navigation Map Journal Narrative sections from Main Stage features.
I built a really simple Story Map Journal in both ArcGIS Online and Portal for ArcGIS to test, and followed the steps outlined by Cooper Thomas in his blog post. Since I'm not using WAB for Developers, I had to download the source code from GitHub and I think i followed the instructions correctly, that is - until I got to the last part and became instantly lost:
So, after some more research, I found another post on How to Publish a custom WAB application to Portal. Which initially gave me hope because @JakeSkinner provided this awesome screenshot that made things seem clear.
So I copied the custom code to my server, and followed the same steps as above and successfully added the application to my Portal (brief moment of success).
When I open try to view the application, I get the following server error.
Any idea what I should do from here?