Cluster not loading, can't find errors... what gives?

I’m getting back to an older file and an important cluster is not loading. It’s showing up with stripes and an attention icon, but right clicking, double-clicking, nothing is telling me why it’s not loading. Any way to figure this out? I could just delete and re-add but there are a LOT of wires to get right, and it’s been a coupe of years…

Maybe there is someone who has a quick solution. I think I would start with setting up an older version of Rhino and hope that it can be opened there. Then copy paste to new version to get grip on the issue.

I experienced the same issue with one of my clusters. I ended-up by deleting the thing.