[Friendly_flyer]

According to Zorin it's the number of image files in play that makes for the big drop in FPS. The various BMPs are up to 10 times the size of the 3D mesh files. It is possibly that the same number of objects that cause stutter will run smoothly if the image files where smaller (128 x 128 rather than 512 x 512). Some objects have smaller image files than other. Some objects have simplified meshes when seen from a distance (from 300 meters away, the factory building with three chimneys get triangular chimneys), which would decrease workload on the computer if viewing a simple object, but a drop if there are several objects at different distances.

Loading time of maps seem mostly correlated with number of objects.