OpenMW Content Editor
A replacement for the Morrowind Construction Set.
OpenMW-CS is a content editor for OpenMW which gives full control of the game's content and the ability to create new content, games and mods.
While initially similar to Bethesda's "Construction Set" for Mororwind, it is now fully independent and can be used to create mods, games and other content that do not depend on Morrowind.