I've been playing CMBN, CMFI, CMFB, and CMRT since last fall, v.4 for all, using Windows 10 and latest nVidia driver (391.35 / 3-27-18) and have recently begun experiencing crashes with CMRT. Had one quick battle crash multiple times. Had a three-hour stock scenario do fine for the first two hours, then crash (as I was trying to save!). I have no AV program other than Windows Defender.