Steps to reproduce:

• Start a fresh Jenkins 2.32.3
• Install latest BO 1.0.0-b24
• Create a Pipeline (even empty)
• Click on the configure cogwheel
  => 404

It seems like it incorrectly prepends the root URL with /jenkins (reminds me of a similar issue like 6 months ago, going to search for it)

Jenkins is indeed running on http://localhost:8080 and clicking on the wheel leads to http://localhost:8081/jenkins/job/pipeline/configure

Can provide more details and/or a screencast if you cannot reproduce for whatever reason.