I've identified the issue with clicking rocks that have already been mined. I'm working on a fix, should be live next time an executive pushes. The code I had was working before the osrs update, I'm not sure if there's a client bug which is making it break but I'm pretty sure I can work around it.
Seems to be a tricky one, for some reason the GameObject query is returning empty rocks, and the empty rocks have the valid colors even though they shouldn't...
I'll most likely disable OSRS compatibility until I can fix this issue.