Techincally it's not a CMD window, it's VMM's CMD window
But yes, you may need to use it. Keep reading.
The crt range lines in a monitor preset define what modelines VMM will allow you to add. You need to make sure you have a monitor preset that covers 25kHz horizontal scan rate, and that will allow the right number of lines (vertical resolution). Bolding is the scan rate range, then the allowed lines min/max for a progressive mode. (Note the latter are visible lines only, the 496x384@60.000 mode will actually have ~416 lines in total to include the blanking interval, and scan rate = total lines x fps)
crt_range1
24960-24960, 49.50-65.00, 0.800, 4.000, 3.200, 0.080, 0.200, 1.000, 0, 0,
384, 400, 768, 800
Go into the directory where you have crt_emudriver and VMM. Open the monitor.ini file, and study it until you find a preset that contains a range line that looks like the above. There are probably other range lines in that preset, so make sure all the modes you want to use are covered. (CRT's often sync to distinct bands, so do not presume you can just add one, wider range line where multiples exist now). If you’re not sure what preset you used, open VMM, check which preset, and copy and paste it giving it a new name because you don’t want to remove any information. Then add the range line above or something like it. Now select your new custom preset in VMM, then click ok to go back to the main black window and use the instructions below.
>>modelist import
This will load your existing modelines from the driver. Make sure the correct mode list has been loaded, by typing.
>> modelist list
Study this list to make sure it looks right, and resembles the contents of your user-modes.ini file of whatever it is. Now you can add a new mode to the RAM list, by typing, e.g.:
>> mode add 496x384@60.000000
Now, list all modes again to make sure the mode is added to the RAM list:
>> modelist list
If this mode was not allowed by your range line, it won't be in the list. Finally, if you're happy with the resulting mode list, install it to the driver:
>> modelist install
This should get you your mode. You could also just add the mode you want to the user-modes.ini file, and then reinstall all modes as per Calamity's crt_emudriver install guide, but if you've made any adjustments to size or timings using ArcadeOSD, or any changes to the sizing in MAME, these will be lost. If ALL you want is the 496x384@60.000 mode, no other modes at all, consider using the Arcade_25 preset.
Further reading is in the monitor presets sticky of the GM forum –
http://forum.arcadecontrols.com/index.php/topic,116023.0.htmlAnd section e) of the guide I wrote up -
https://www.aussiearcade.com/showthread.php/87668-A-guide-to-connecting-your-Windows-PC-to-an-SD-CRT-TV-PVM-or-Arcade-Monitor