File structure has changed, delete old version if updating from 1.2.1 Attribution-NonCommercial-NoDerivatives 4.0 International Mk3 Shuttle Pack (aka Shuttle Lifting Body) is required to use this add-on. Shared textures are engines>CA_STME and shuttleStack>CAet Attribution-NonCommercial-NoDerivatives 4.0 International  - If you like what I do and would like to donate it would be appreciated   If you would like to see a mod support