For development I find it useful to clone the live system to localhost and do the trial validation when needed. I noticed a bunch of error messages reporting "counter" as an undefined variable when using ads, and thought I'd send a fix for it:
in components\com_chronoforums2\chronoforums\themes\default\views\topics\advertisement.php
Change
in components\com_chronoforums2\chronoforums\themes\default\views\topics\advertisement.php
Change
if(!empty($this->get('settings.adverts_code', ''))){ to if(isset($counter) && !empty($this->get('settings.adverts_code', ''))){
