If I install this in the garage and occasionally park my car where water may drip, are there concerns for mold or moisture to form between the interlocking seams?

Our Dura Lock Rubber Tiles are mold and mildew resistant, so there would be no concern there. The only concern that we would have is with any potential oil dripping from your vehicle. Oil can cause the flooring to breakdown over time. To prevent this, we recommend placing one of our Nitro Rolls in the area you park your car. This will ensure that your floor keeps looking great for a very long time.