HUD Visible by me but not for other people

Hi, Little pbm here.

I see well the HUD, but for other people, they can show it.
When one try to /panel show, I have this in log file : 

[Error] Failed to call hook 'CmdHide' on plugin 'PanelSystem v1.1.9' (ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index)

Thanks

Changed Status from Pending to Fixed

Changed Fixed In to 1.2.0