Discussion about any issues you are facing with path builder
I have one question, are you running some crons when editing the paths, if yes can you explain why?
Because I see in the drupal report that a cron was running, and the location and referrer points to the wisski plugin:
I got an xml file that holds path information from another wisski system.
How can I import this file into my wisski system to be able to use those file?
Drupal views is a bit of a Drupal in a Drupal. It has its own (entity) query, its own fields, ... This blog (part 1+2) helped me a bit to understand what's going on in views and how to implement views for a non-SQL-based entity type. Also, the EntityFieldQuery Views Backend module provides valuable code. Unfortunately, the D8 branch is currently defunct/not properly migrated.