It's a shame post production was rushed to meet the release date, resulting in dodgy matte lines and such. Douglas Trumbull couldn't have been too happy having his name on the final product.
I've been wondering if the raw FX footage was saved. TNG used a shot of the Klingon cruiser a few times in the early seasons, only it had a new starfield behind it. And the engine glow was changed from red to blue.