A few things I encountered:
There was an issue a few months ago, where an email that was identified as spam, and had the X-Spam/X-Spam-Flag header added, wasn't being moved to the Junk folder. That was fixed a few releases back, now it works.
I also noticed that adding an email address to the email whitelist (in the panel UI) doesn't work 100% of the times, having some of the whitelisted emails still going to spam. Adam told me they were looking into that. Still not fixed.
I found some files at
I always wondered how do they work. If they have something to do with teaching rspamd about spam behavior or maybe they are something not implemented all the way.