some scenes despite my best efforts remained very laggy.
These scenes have been shelved and removed to save install space as well as to result in more consistency in the performance of the scenes.
The general problem is that high-resolution meshes are designed for environments where culling can occur within a short viewing distance, as most gameplay occurs in a local space. however, this is a flying game therefore visibility of the environment is crucial for the player to be able to maintain orientation during maneuvers. It is not impossible to make these scenes run better however it is a bit above my skill level at present.