Hi, Ulrik 

Firstly, I would like to sincerely apologize for the delayed response as we have been experiencing an unusually high number of tickets and we had a break during our National Holiday, which additionally slowed the response time.

 I am sorry that it has taken longer than usual to respond to your concern and your patience is highly appreciated.

-

It seems i found a solution with some custom CSS, while playing around on our Demo Sandbox site.

I found two elements that you can manipulate with CSS for the width, this one :

.modal-dialog {
    max-width: 1200px !important;
    width: 1200px !important;
}

But then i also add this CSS, in order to get it to look more centered, for the other element :

.modal-content {  
  max-width: 1200px !important;   
 width: 1200px !important;}

Now, it looks like that, it seems more centered while being able to set a custom width.

So, both CSS combined :

.modal-dialog {
    max-width: 1200px !important;
    width: 1200px !important;
}
.modal-content {
    max-width: 1200px !important;
    width: 1200px !important;
}

If you need this only for one specific table, add this to table settings/Customize/Custom CSS,

but if you need this same style for all tables, copy it to main plugin settings/Custom JS and CSS/Custom CSS.

Let me know if that helps.Thank you