Replacing the seals on your refrigerator is not hard and can make a big improvement in the aplliances efficiency (and appearance). Replacement seals are often available at many home goods store and through the maker of the unit. One tip for using these replacement seals is to warm them before installing, this removes the crimps that often occur from their packaging. A few minutes in the clothes dryer should do the trick.
If vibration causes nuts to constantly work loose, first add a lock washer, if it doesn’t have one. Or, if there is room on the bolt, use two nuts, tightened toward each other so they lock solidly. You can also try wrapping monofilament fishing line under the nut before tightening it on the bolt. Another possibility is to try wrapping the threads first with the teflon tape that is used in plumbing.