My problem is simply that the "Test Result" option is not shown in the Job page.

I have installed the plugin, and in Job Configuration I have added the Post-build Action "Publish Cucumber test result report" with options: Cucumber JSON report files: 'features/reports/results.json'

My cucumber exec build step looks like
bundle exec cucumber -f pretty -f json -o ${WORKSPACE}/features/reports/results.json

Trying to visit /job/ft/job/dev_pp/32 (the latest build) I do not find "Test Result" in the job side-panel.  I also have the "Cucumber reports" plugin enabled and "Cucumber reports" does show up there.  I saw in your screenshots that you are using Jenkins 1.x, maybe this is a regression in 2.x

If there is some step I skipped, then I would make this a documentation bug, I think I have read the instructions carefully.  I have not tried building and installing your latest/unpublished release, so I can't say whether this is already fixed in HEAD.

I would try building this and I'll be glad to contribute a fix if possible, but if you've already heard of this issue and know where the problem might be coming from, or if you can at least reproduce and confirm the bug, it would be great to know that it's not a user error before I go to that extent.