It works well now thx  for your explains

Tutorial is from 2017 with older version of iClone7. It does not even have Attach option for the Camera (should've been between LookAt and Path).
RL has change the behavior of the Root since.

Now, if you still wish to use a Link, then select Clip, from right mouse click menu select Motion Modifier and just click OK. It is going to make the Root fixed. Then it's going to work as you intended.

It works !
But in this video, Walrlord720 click in "linkage" and it works !
https://www.youtube.com/watch?v=tohyMlNAOdc&t=335s&ab_channel=WarLord720

Why does it work for him and many tutorials I saw and not for me ?

Anyway thx for your help !

Instead of linking, attach and then disable Rotate in the Inherit.

Oups ! I fogot to save the changes.
it's fixed

It is still private...

I's done !
thx

set the video to public so we can see the issue.  

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That's what I did...This is why I don't understand it doesn't work...
This trouble is the same in iclone 7 and 8.
I checked the parameters and I noticed nothing strange...

The only way I found  to fix it , is to create a cube, attach it to the rl_boneroot and link the camera to it...

Try linking to the rl_boneroot (top most selection in the dropdown)

93% of original size (was 539x16) - Click to enlarge93% of original size (was 539x16) - Click to enlarge