I have the same problem...!

let me Quote the answer for you:
The issue of not being able to close certan screens (Pirate one a beggining of game) is caused by custom government types. This events button dialog is based on the govenrment you are, if you don't add your type to the options, you can't close the dialog. The code for this can be found in event/pirate_events.txt

So i had to start a new game without custom government types which means it was caused by the 99+ ethics mod and not by this mod!

I just want to point out how stupid it is that the game triggers an event for any government, but doesn't allow you to close it unless you're one of the standart governments. They could have implemented some sort of default option if you don't play as one of the listed governments. I guess this makes modding these events a pain in the a**, because you need to add your new government to each single one of them.

I wonder why no one has addressed this at a bigger scale... took me some effort to find out / get the needed information about the solution. Hope they will fix this soon / or even notice...