Regarding opting out, from https://www.mediawiki.org/wiki/Extension:LiquidThreads:
To deactivate LiquidThreads on a specific page on a wiki where LiquidThreads is opt-out add
{{#useliquidthreads:0}}
Should work, though you'll lose the current replies (IIRC)
-- Yuvi Panda T http://yuvi.in/blog