So to simplify: Official.esm NOT loaded = GMST contamination
If you make mods for Morrowind you need to be aware of the implications
of loading or not loading an official ESM file that you have installed
on your system.
Whenever you save a plug-in, that mod becomes dependent on all
ESM files that were loaded into the Construction Set. This is
fine if you intend to use expansion material in your mod, but
if your mod does not use expansion items or script functions,
it is preferable to only keep the Morrowind dependency.
However, not loading one or more installed expansion ESM files
leads to GMST contamination, and you as a modder need to be aware
of when these entries are being dumped into your plug-in file,
how to avoid them and how to remove them.
The only way to avoid this problem is to have ALL installed official
ESM files loaded, or run several different installations for corresponding
If you choose to load all expansion .esms, the mod will then become
dependent on those master files. Once the mod is completed, the
unwanted Parent Master entries can be removed. This is fine if you
know you are not using any items or script functions from the ESM
file you are removing, but it is not always possible to determine
what item belongs with which ESM file. Removing a dependency when
the mod uses those items is a sure way to corrupted your file.
There are several ways in which these GMST entries can be removed
from a plug-in file, but using the 'Details' section of
the Construction Set is not one of them. The GMST entries can be
toggled as ignored, which is fine when playing the game, but as
soon as the mod is saved in the editor again, the entries are re-entered
into the file.
There are several utilities available that can permanently delete
GMST entries from a file. Enchanted Editor, TES Plug-in Conflict
Detector, TES Advanced Mod Editor, TESTool and GMST Cleaner are
all capable of removing these unwanted GMST entries from a file.
If you use mods, it's always a good idea to scan new mods for
any possible GMST contamination. Many people still do not realize
they are being included in plugin files, and even those that do
know can sometimes forget to remove them (especially for rushed
updates) before deploying.
If you have already included a contaminated mod in a savegame, I
recommend NOT deleting the GMST entries in them. Modifying a plugin
file once it is included in your save game can lead to a Dirty
. This occurs because the data stamp on the file
is modified, which then changes it's position in the load order.
When this happens, the game cannot match cell reference indexes
with the file that it originated from, and you end up with two objects
instead of one.
To fix this, ManaUser has created a very useful little mod called
QuickFix. This mod loads last and 'resets' the GMST values to
their correct values.
If you are making a total conversion, it's important that you
include all of the CORRECT Morrowind GMST values. Excluding the
GMST entries has the same result in-game as including incorrectly
defined ones in your master file. This is especially important if
you are creating your TC files completely from scratch. The easiest
way to obtain the GMST entries from Morrowind.esm is to use the
import/export feature of the Construction set. Simply export from
MW.esm to a text file, and then import the text file to your own
master file. If you have already started a TC from scratch and already
have these incorrect entries in your files, you can load up your
TC file AND Morrowind.esm into the CS and save. This will update
all bogus GMST entries to their correct value, but it will also
make you file dependent on Morrowind.esm. This dependency can be
removed from your file with the Morrowind Enchanted Editor or The
Elder Scrolls Dependency Tool Kit.