Exploding Launch Pads

Has anyone seen this? I figured out how to set a launch point on the east coast of the main continent on Droo. The stock launch point is in the center of the continent. To test the launch site, I built a simple rocket and pad ( from modular launch pad mod- great) in the 1 to 1 scale. I launched from my new launch point with no problem. When I tried to launch one of my rockets with launch pad that is built to larger than 1 to 1 scale the pad and rocket explode as soon as the launch screen appears. It's as though the pad and rocket falls from the sky and explodes. It happens so fast I can't see the cause. Large scale rockets and pads work fine from the stock launch point.