Yeah it makes sense that rct2 didn't take as long to load as rct3 does. Every object in the park (i.e. paths, benches, coasters, trees, flowers, terrain, peeps, lights etc.) needs to be rendered in full 3D. rct2 just needed to load in some sprites. rct3 is much more graphic intensive. No Limits run using OpenGL and rct3 uses Direct 3D or DirectX, so that's the difference there. I also can run NL with better frame rates than rct3. Go figure.