A2A C182 crashing FSX

Hi All. Quick question. I recently bought the A2A Cessna 182T, (and for the most part, love it to bits.) But, it does seem to have one drawback. If my flight is more than a few minutes, or if I do something like check the map, (the default FSX map, not the A2A map in the cockpit.) FSX will freeze up, or scenery will disappear, or the plane will disappear, or all of the above. Has anyone else had this problem and does anyone know a cure? As I said, I really love this plane, and I would hate to not be able to fly it. Thanks in advance if anyone can help.