That does sound odd.
Just to check the basics, post a couple photos of your hardware so we can see how you have things set up. A photo of the board itself that lets us see the solder joints, and another that lets us see all the connections between the display and your Arduino will get us rolling.
You can attach images directly to a post, or just use URLs if you can store images somewhere else. If you want to use attachments, the system prefers (well, demands) 800x600 or less.
When you void a product warranty, you give up your right to sue the manufacturer if something goes wrong and accept full responsibility for whatever happens next. And then you truly own the product.