Hello , 

I need to create a simple pop up windows for general messages purpose on the main page of the board.

It's possible on Invision boards without modify code or skin?

thanks

Is this what you are looking for? Scroll down to Announcements.

 

Yes, but I don't know why many of these options doesn't appear on my Moderator CP ...

 

 

You dont have permissions on the front end. You need to check Members>Staff>Moderators, and ensure you have permissions for everything in there