Not working, the game just closes before begin of the game map display.

What isn't working? Which settings? Which patch? Which mods installed? Don't make us asking the same questions over and over again, instead provide enough information so technical support can be provided. Thanks.

The AI pack is installed and it is not working for 1.6 game data 1.6 RC as soon as I put barbarian and begin game it closes.

Here is the screenshot attached. PFA

All visible option is not working and Romans is not playing celts is playing.

Here is the screenshot attached PFA

multiplayer online not working although for the same map and settings 1.6 RC 1.6 Game Data Barbarian. It just shuts down screen.

ok thanks, I can enjoy it alone btw it is good to play with barbarian. I cannot do this in DE steam.

Barbarian can not play with the new civilizations, that's why, if you put Random or Full Random like I see in the picture above, it doesn't work. Use the AoC Random or HD Random like Chris suggested.
As for the crash, it should have nothing to do with the AI. Send us the event viewer report so that we can identify the issue.

What is event viewer? and where should I download it? Only 1v1 is working 2v2 1v2 2v3 and above are not working.

Click the link below and scroll down:
https://www.voobly.com/gamemods/mod/1519/v16-RC

Here is the event viewer report, it repeatedly have errors.

It is working excellent for 1v1 conditions when I put even 1v2 condition it just crashes. The conditions I selected are attached below in screenshot. PFA

Here is the video of how it is crashing.

Indeed it happens. I have no idea why but I will test a bit. My hipothesis is that some of the new features we've added clash with the Barbarian code, which may be a hard fix without the help of the creator.
You can always try the normal "Computer" that comes with the mod and give it handicap if it's too easy for you:
https://www.voobly.com/gamemods/mod/1587/16-Custom-Creator