I installed a Quickstep laminate floor 4 years ago. The laminate is bubbling in several places. Quickstep has a 20 year warranty, but has denied my claim. They say I used the wrong pad under the flooring. I used the pad that was recommneded by the retailer and in the Quickstep installation material. Whom do I sue. Do I file in the county I live or the county I purchased the material in. Quickstep will not provide me with a denial letter, do they need to? What can I ask for in damages, material and labor, court cost.