for pistol, listen to @nerdle. For those demo's, did you put your et in dominationmod before launching demo? - if so can you send one of those files so i can check myself.
PS: why do people keep on recording in ET itself (ok i get it for cheaters, but if its for fun no), it's 2018 people wake up Millions of free recording software out there waiting for you. No more mess with dm84, better quality, what are you all waiting for?
For Nvidia users => https://www.nvidia.com/en-us/geforce/geforce-experience/ best tool ever and easy to use.
For all others just google game record software Don't waste time on dm84 files