Hey Duncan, I’m really sorry for the issue you’ve come across here! This is something Guru's Technical Support team can best respond to - I've alerted our Support team and they’ll be touch as soon as possible over email to troubleshoot with you further.

Thanks, a support request has already been opened. However, I assumed I was just doing something wrong which is why I’ve posted in the community form.

Are you saying this is a bug?

Oh, good! Thank you for reporting  Seeing as we had yesterday’s hierarchy update release and the nature of the issue here, it looks like this could be a bug to me. Our Technical Support team will be able to assist with troubleshooting and escalating internally.

Hi Duncan, thanks again for bringing this to our attention! I have an answer from the Technical Support team that I’ll share here, as well.

The updates made to hierarchy in Guru this week did have an impact on Knowledge Trigger creation. We have a subsequent the Knowledge Trigger user interface update scheduled to release next week. In next week’s update, we are removing the (not frequently used) ability to create folder-level Knowledge Triggers. In its place, we will offer a redesigned and simpler interface, including a multi-card Card picklist when assigning the knowledge to the Knowledge Trigger.

I’m really sorry for the inconvenience this causes and for the confusion here. As a next step, I’ll convert this question to Product Feedback so that other users can share and “upvote” the idea to include folder support for Knowledge Triggers. Fortunately, it won’t be too much longer we’re in this inbetween state, as the Knowledge Triggers update is scheduled to release next week (note: our offices are closed Monday and Tuesday for the July 4th holiday).