So what sort of morrowind error are gmst's? What does gmst stand for? I've seen so many mods with warnings of: This mod got gmst's and dirty refs! Watch out! Ussualy i don't download a mod then unless its very good, but now i still don't know what exactly it means. So... anyone?

GMST stands for "game settings". In straight Morrowind (i.e. without Tribunal or Bloodmoon) these aren't of any consequence. With the expansions installed, however, they can cause problems, probably because Tribunal and/or Bloodmoon change these settings. I don't know.

Thus, when releasing a plugin, one has to use a third-party program like Morrowind Enchanted Editor or TESTool to delete these entries. Otherwise, names of things can go strange, quests can break, moving objects can double, among other problems.

Here's a page that explains a bit better.

Don't use MWEE. MWEE was not designed for this, and will show you all the GMSTs in one category. While most GMSTs are unclean, some are legitimate. Deleting the entire category will trash some mods.

If you're just looking for a quick fix, then TESTool is the way to go, but it will cause problems with some of the more unusually-coded mods when you're using TESTool to attempt to clean them. If you're looking for something that shows the unclean GMSTs, among other problems, and allows you to decide which ones to keep, try TESPCD.