There is no wrong screen size, only hundreds of right screen sizes

Sites made with VSD tend to be pretty consistent across browsers, and screen size shouldn't have an effect on display since these aren't fluid or responsive sites.
One thing to try before anything else, go to Your Account > Your Purchases and download the latest VSD version. See what things look like then.
Maybe consider some other options for your menu. You could use the Buttonizer in VSD and create 5 separate buttons; no need for the '.............' in between them to space them out.
You could also make your buttons in a graphics program then insert in VSD and add the links.
Let us know how you're getting on