Manage Extension not avaialble with Premiere 2017 Trial license?

Hi,

I've just installed Premeirer 2017 with a trial license and have been given a zxp file so I can add an extension.

I have been told I can add this through "Manage Extensions" but I can't find this option (certainly not in the same place as it appears in my licensed premeire 2014).

Am I missing something simple here?  Do I need a full license for this option?

Thanks Dave