I have been going through the MSGO mods to see how they are working and I had a question on AtmosphericSoundEffects-3.0-Tribunal.

There is an empty external cell, -15, -8. This cell does not have any references, but has its region changed from 'wilderness' (in morrowind.esm) to 'bitter coast region' (in AtmosphericSounds).

I cannot see a reason for this change to exist in this mod. I know that internal cells can be used for 'junk storage', but I have never heard of a reason for an empty external cell.

I have used tes3cmd to search for any scripts that use 'position', 'PlaceItem', AITravel, 'AIFollow', and 'AIEEscort' to see if there might be a script that is using that cell, but have found nothing.

So is there any reason for an empty external cell, and if so, what else should I check?

Thank you for any information!

As you know, in the vanilla game that cell is set as Wilderness, instead of NO CELL, which means it shows up as white on the region map... (probably just a mistake left over from the devs.)
Since Bitter Coast is the default Region selected my guess is that someone clicked on that white Wilderness cell out of curiosity, which then set it to Bitter Coast.

That's the only thing I can think of, since there would be no reason for that mod to alter the cell.

There would be no harm in removing this edit, as it won't have any effect on anything.

Thanks for the reply!

Is there ever a valid reason for a mod to have an empty external cell? (Or internal cell, other than as a "junk" cell)?

In Wilderness Sounds, changing that exterior region maybe was meant as a fix of vanilla as surrounding cells are of another region (e.g. I'm changing a lot of cells, I noticed this, why not fix it, can't do harm.
[EDIT]Ah no, sorry, now I've seen cell is far from other regions, probably not worth touch it and "fix" was a "typo"

Interior "dummy" cells are sometimes used also as dialog filters (e.g. Mournhold, Solstheim, Firewatch Library). I think in this case TESTool is smart enough to not delete them even if empty

I believe it is a construction set bug, I have never deternined the reason why, but many mods and even the two expansions have that cell reference, plus about 6 or 7 empty cell references in the Bitter coast region regularly crop in mods

None that i am aware of.

Thank you Pluto, abot, and Slartibartfast1 for your detailed answers!

Empty cell references are indeed quite spread and it often happens that even tes3cmd leave them in and does not clean them. In this case, however, I believe the mod was built from official bitter cloast sounds plugin, which actually contain this change. I noticed it when I was going again through all the plugins after you pointed me to the dirty references that were still present and I cleaned this reference in latest release.

Thanks WH-Reaper, I have found that comparing your modified official mods to the originals to be very enlightening! I have a follow-up question.

I have found several mods with CREA and NPC_ entries that are cleaned by TESTool. Looking closer, I find that the entries only differ by their Unknown_2 entry in the AIDT field.

In testing, I have found no problems with these entries removed. In many (but not all) cases, the Unknown_2 entry is changed from 0x0000 to 0xffff. Since the use of Unknown_2 is, well, unknown, does anyone know of an adverse effect of cleaning these types of entries?

Thanks for the information, this is very helpful.

Well thanks And thanks again for pointing out the dirty refs I left there.

Yeah, I found one too. Now if only I could remember what I have done with it But I think I cleaned it. No idea what it is for.

Btw. I also cleaned references in Area effect arrows to all vanilla unenchanted bows and xbows, which had for some reason slash and thurst damage changed from 0-0 to 1-1. No idea why (it is also interesting that enchanted bows were left untouched).