With ffmpeg it literally takes out what you want so you can use it later. Eg. below -ss means starting time is 16 minutes and 30 seconds and -to means extract until 17 minutes and 23 seconds
-i = the input file
output file = CCME-flash-and-2-phone-setup-final.mp4
ffmpeg -i CCME-flash-and-2-phone-setup.mp4 -ss 00:16:30 -to 00:17:23 -c copy CCME-flash-and-2-phone-setup-fin........
The strange thing is that usually the first install or two will work on any new machine but then it suddenly won't. I had this experience on QEMU 2.13 on a different machine. There is something finicky or buggy about the CUCM installer even when choosing the same virtual hardware specs.
QEMU PC emulator version 0.12.1 (qemu-kvm-0.12.1.2-2.506.el6_10.1), Copyright (c) 2003-2008 Fabrice Bellard