The previous stable release is available at the Morrowind Nexus, but is now bundled by default with MGE XE 0.10.1.
The stable release does not include Lua support.

For mod authors, the best way to learn MWSE and get assistance is to ask questions in the #mwse channel of the Morrowind Modding Community Discord.

The existing documentation is incomplete and partially outdated, but it can still be a useful resource, over at mwse.readthedocs.io.

The Morrowind Script Extender is free software, licensed according to the GNU General Public License, and comes with ABSOLUTELY NO WARRANTY. See the file LICENSE.TXT for details if you are interested in distributing or modifying the program.