Hey Clément,
I am not sure wether others have mentioned that before. When the filter settings in the option page have been set the way, that the tags generator can´t find and add tags to a thread and the option "Automatically process all pages" is selected, then while running, on the first page threads are stuffing up with 0 tags - until the site reaches the "Process X threads per page" limit. I´ve already streched the limit to 500 threads per page, but that doesn´t help, since even that limit is reached and the tags generator stops. It would be a great help, when the tags generator would fetch all threads matching the filter setings and could then disregard those where he can´t add tags on a per run basis. That way, when a thread has received more content and has become "tag able" with the next run, the thread receives his tags but the stuffing won´t occur any longer that triggers the generator to stop.
And what I really would like to ask you to implement, I guess I begged for that already after initial release, would be to add a xfcron job. I guess most of us forget about running the generator frequently and I am always surprised, how many threads need to be "tagged". That would be a major improvement, like a fire & forget system.