We have been working to implement the Utility Network (with the 2020 UPDM data model) in a Postgres database. Throughout the process, we've gotten many errors similar to this:

There was no real guidance on what was wrong or how to fix it. We spent two days or so looking into different possibilities. As a part of that work, we exported the asset package to a file geodatabase (Postgres) and were able to see what the issue was in less than 15 minutes; as show in the screen shot below.

Would it be possible to provide more detailed information in the errors that are provided through the Pro interface?