Is it possible to set a default filter for all users ? Is it possible to forbide the "all" filter ?

No, it is not possible to set a default filter at this time.

Is it planned to modify the ASSET of the module to be able to put the same parameters as in the filter?

No, but there are plans to add additional assets that CB GroupJive can properly interpret for the output you're wanting (e.g. probably something like user.mygroups, user.joinedgroups, etc..).

I click on groups or relations tab, filter is ok, so i'm not on the "all" tab.
I wait, update comes but charge informations from "all" tab, not my filter.

You mean when it updates the stream with new activity entries it's not using the filter you selected? Could just be an issue with the stream refresh URL, yes. Have added a bug ticket to investigate further.

forge.joomlapolis.com/issues/7964

It seems that the options of automatic update or automatic loading do not exist in Groupjives (activities or wall).
Is this correct and is it planned?

All stream features exist for every stream. The activity stream in CB GroupJive Groups is output by CB Auto Actions and its System Action responsible for that. It has that feature configured to "Same as Global" so whatever is configured in CB Activity > Parameters will be applied there unless you make a copy of "CB Groupjive - Stream" and edit it in the copy to force it on just for GJ.

There are two tabs in a group, an activity and a wall.
Is there a difference between these two tabs?

The activity tab is powered by CB Activity and output by CB Auto Actions. The Wall is legacy GJ Wall integration that has been basically replaced by CB Activity usage, but not removed yet. GJ Wall be going away in a future update once CB Activity streams have been improved further for easier integration with other plugins.

Then that feature should work perfectly fine. Are there new posts for it to even load in? If the stream takes too long to find new posts it will give up to prevent someones browser from pinging your site constantly. Easy way to test this is open a group in 2 different tabs. Make a post in 1 of the tabs. Now wait for the other tab to update. This seams to work perfectly fine in my tests.

Note it does not auto update instantly. This is not a PUSH system. You would need a websocket backend for that which PHP is not. This means it is a PULL system and it does this by polling your site with an http request at specified interval to see if there are any new posts. The interval is configurable within CB Activity > Parameters > Loader if you want it to check faster. By default it only checks once every minute and if it fails to find new posts by default 60 times it will give up.

As you do not have an active subscription it is also possible you have an out of date release of CB Activity where this may not be working reliably.