I've been testing this since I installed it last week and working on moving my entire board to 6.1x, but I'm now delaying as I'm seeing the same behavior everyone else is mentioning.
As a guest on the board, the first time the page loads, I see WOL on summary, but if I go into a forum and back to summary, WOL goes away, UNLESS logged in.
Additionally, I'm seeing the same thing everyone else is on the rebuilding forum stat files, "Cannot find any forum_thread_data files".
If I copy the forum_thread_data.file out of the hidden directory under the forum to the forum directory, it deletes that file and gives the error! "Cannot find any forum_thread_data files".
BUT, if I copy all the data from the private directory up to the forum directory rebuild works. Of course this is similar to unhiding the forum itself.
So, looks like we have an issue with WOL hack, and how UBB rebuilds forum stat files. Hope to see some ideas on this.
Zackary