They finally got it right!
Enter the addon "Marines" which also includes the 1.10 patch. It is the 1.10 patch that is the big thing here, even though I love the Marines stuff too. There are a large number of improvements in version 1.10 that suddenly gets the CMSF engine over the hill it's been struggling with since the disappointing version 1.0. Suddenly the game is FUN to play. Really fun! Now I play the game and think of the tiny marines down there as soldiers - and not heaps of pixels doing irregular things. In version 1.0 they would disembark from a Stryker IFV under fire and just stand there confused getting gunned down. In version 1.10 they automatically find the best cover available and rushes there - some of them stopping briefly to return fire. When fighting intense urban combat they do it the way I ordered them - instead of getting stuck outside a house when a Syrian MG cuts them down. The difference is enormous. CMSF Marines i now the best tactical combat simulator out there - no doubt!
Some bugs remain though, the path finding for vehicles can fail sometimes etc. I am sure that Battlefront will fix this, and it works good most of the time...
Right now I'm really looking forward to the day when Combat Mission returns to WWII with this engine!