I guess ACE was causing a problem. Luckily, as soon as I opened a launcher, it upgrades ACE and it works fine now. Note: Neither A3_ACE compatible mod Nor Ace advanced ballistic mod were needed to launch the mission successfuly. Anyway, thanks for your advise.

Hey! Are you sure you have all the required items (ace; CBA_A3; Cupterrains-core; Cupterrains-maps) downloaded and plugged in?
Do you get the same message in every scenarios which requires ace?
If yes, maybe you could try to reinstall ACE and give it a try again.

I am keep getting a message "ace_advanced_ballistic.dl is missing" I download advanced ballistic mod V3.5 and copied .dll file into dll folder and config file into config folder. But still it is not working. am I missing something here?

Thanks for your feedback! I designed the mission specially for a small squad which has only 3 guys (the recon units) with supressor on their guns. And yes, the ending trigger sometimes works and sometimes doesn't, im looking for the source of the problem, will update it as soon as i find it. Hope you enjoyed it though!

Great mission, two things though. I didn't have a suppressor and the ending wasn't triggered.