OK let's get things clarified here.
The ONLY thing where there are any licensing issues is the NIF exporter (which for Morrowind was released for download some time after the game shipped, and is NOT, I repeat NOT part of the Construction Set). Also, you MUST have 3D Studio Max -- a program that can cost hundreds and hundreds of dollars -- to use the exporter in the first place. The exporter is used to convert files from 3D Studio Max format to NIF. Hopefully the licensing issues can be overcome and this tool can eventually be released. That is what Maverique was talking about in her post yesterday.
The Construction Set you'll be able to download from elderscrolls.com is the EXACT SAME TOOL that we use to make the game. It isn't dumbed down. It isn't crippled. It has all of the features we used to create the game world, define objects, put them in the world, create quests, dialogue, scripts, etc. You will be able to do ALL of that with the Construction Set you download from elderscrolls.com. With no restrictions.
Is that clear enough?