Just timed CMNAO, CMO, and CMO starting up on an i7-9750, nvidia 1665 ti, 32Gb RAM, and SSD...
CMNAO - 11s from icon click to main screen
CMO - 18s from double click on icon to main menu
CMO Steam - 24s from icon double click, through matrix dialog, to main menu
One of the biggest differences between CMO and CMNAO is loading the scenario. CMO is lightning fast loading the scenario compared to CMNAO.
I also did come timings of Op Brass Drum on all. CMO is 30-40% faster in processing the game at its fastest over CMNAO.
So overall, CMO takes a little more time (6-7 seconds) to load the game from a dead stop, but its incredibly faster load and running scenarios.