It was actually on last night but with nonupdated stats from what looked like S3/4. It's gone again now.
The addon was updated with Riot's API (with a higher rate dev api key too I believe), but it seems like the stats were breaking with every major LoL update anyway. @Dark has far less time to work on unpaid side projects these days, since he has a full-time job at Jagex and also has to maintain his paid XenForo addons. I doubt that Riot would allow a paid LoL stats addon using their API, so there's very little incentive to work on it (or other free XF addons). I don't think it would be worth the effort to be honest, because it would be broken again in the next update. At that point, he'd be forced into maintaining an unpopular (I assume he has analytics data) stats page at the whim of Riot.
Basically what @Gaw said Riot designed their API with backwards compatibility in mind (pass a version number on each call, get consistent results back), but for whatever ridiculous reason they very aggressively deprecate older version numbers, so just a couple of weeks after writing something it will no longer work. And it's not just a case of a few different fields, they completely change the structure of the data, e.g. inlining lists that were previously separate id-indexed lists or moving them to a completely separate API call or vice-versa to both. It's nontrivial, time-consuming and dull work to keep up with Riot's API. There were a couple of people who voiced interest in a paid plugin, but even at a very premium price and/or charging per-update it's still not feasible at such a small scale I might bring it up to date one last time, in the hope that Riot have finally settled on an API design that is here to stay, but if it changes again then RIP
Should be working again now, and can also now handle summoner names with spaces Seems the API actually had not changed much since the last time I updated the script (it was primarily broken due to Riot moving to https only) so it should continue to work for quite a while
