Because WebEasy enables you to do so such with your website, the HTML files that you build can be quite complex. Some older browsers cannot handle that complexity.
Try altering your document design to reduce its complexity. One way of doing this is to avoid having items that overlap. If you do not want to alter your design, you can try viewing your website in other browsers or upgrading to a newer version of the browser you are using.
You should remember that even though some browsers display your website without problems, others might not — and visitors might use those other browsers. You should try to create a website that can be viewed without problems with as many different browsers as possible.