I want to ask is there a possibility to add a Carnage Mode to a list of speedruns ( there could be two categories: Simple completion of CM; trying to get at least bronze in last challenge ends the run. And also CM Gold medals only.)

Done. Tell me if you think something needs to be added/changed. By the way, I could not remove the "Wreckless/Wreckfest" thingie from Carnage Mode Runs, so just ignore them and send run as Wreckfest one ;)