Do you have property linked city prop and player props according in which city allowed to build each upgrade?

Outpost, village, town, etc?

I don't have time to investigate this topic at the moment but will return with a definite answer later as I'm not by CPU at moment to not guess overly much

It can be classified easily as difference between treasury sites, visits, etc that mcu is not available..

However, the stuff from "base" game is very different from dlc.. but I think the answer is within the base game rpk. Mcu is not that difficult to add in general as you look how things are linked in Dlc2 package

But it's either in those three "city logic.rpk, cityproperties.rpk or citypropertieslogic.rpk" I think we at some point created mcu from "aow structure.rpk" for Shadow Realm mod. But time has flown.

Oh and in general have you restrictions for specific races? I guess each race need to have a link to the mcu itself

I did the race link for sure; but the outpost/village/town thingy I don't remember having done it... But I did not do it for any of them and stuff is working for mana node/gold mine and not for the others so that's why I am a bit puzzled.
Could be that mana node and gold mine were setup properly when the DLC 2 came out and not the others.. let me know if you have any other ideas btw and thank you very much for your answer.

Among the various hypothesis I have - one of my active mod is modfiying the RPK linked to a structure and changed the string name associated to it but I really can't think of any so... not sure.

I can return with a definite answer tomorrow.

At least one mod has done it already. https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=636431583

So it's likely doable

Yeah I mean I did make it work for mana node / gold mine but the others aren't showing :(
All the following do not seem to work : great farm / magma forge and all the elemental nodes.

Okey so.

In Aow_CityProperties.Rpk did you link your new city upgrades with new MCU to a new "AoW Race City Upgrade Link Data" without setting Race link?

In CityPropertiesLogic.rpk did you create a "AoW City Upgrade: Normal" and added all the corresponding settings similiar as other mcu? Added the correct "Recured Structure Name" like:

GREAT_FARM, GOLD_MINE, MANA_NODE, MAGMA_FORGE etc

Then added your string of "Upgrade name" to something like "AYALINS_PREMIUM_FARM" or something.

Created a "AoW City Property" for it like "Has Ayalins Premium Farm" and link it to the "AoW City Upgrade" you made for your custom city upgrade. Then did not set anything for "Required CIty Properties" and just used the "Properties"

The "Properties" field also requires all your inputs and bonus and stuff. Maybe someone got 1+ melee damage or whatever from something like "AoW City Property: Unit Property" connected with another prop or ability group.

You might also want to replace the text various text for each structure so they correspond with your mod that they also feature a mcu building through hypertext.

On the top of my head yes to all of that honestly.
1. All my upgrades have Race city upgrade link data without any race link so that it's applied to every playable race.
2. I did create all the upgrade:normal files (they are the files being linked to the race city upgrade link mentioned in 1.)
3. I did fill the required structure name with the proper string.
4. They have an upgrade name as well
5. I did all the aow city property "has my_building_name" and linked them to the files created in point 2)
6. Yeah I did a bunch of them for all of my new upgrades, they are linked too.
7. Text is done as well. Actually they all have a unique new icon as well which I imported using the resource editor and photoshop.

So I don't feel like I have screwed any of the basic things I was supposed to do.
I will try the following :
- Remove the required structure name to see if the building exists and is buildable in game normally without any requisites.
- If it is still not buildable, it means the problem comes from the upgrade files or the race link files.. I think I will just delete the files and redo them in this case, might be a file-ID issue from a bad copy-paste or whatever.
- If it is buildable, it means the issue comes from the string name unlocking the upgrade. I will deactivate all my other mods and only activate this one to see if it works (like I mentioned, I feel it could be that one of my other mod is modifying the string name of structures).
- Eventually, I may want to try writing my files in a base-game package instead of on a DLC2 resource pack. Connections between the resource packs from the different expansions are not that good I have noticed and it could be the issue.
- If all of that this still does not work I am screwed honestly I don't see any other things I can really do to fix the problem.

Clearly.

I managed to make it work with the mentioned site. Problably some mods may edit the same values in your case

https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2812098386
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2812098520
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2812098445
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2812098495

Essentially I just changed the "Required Structure Name"´to test this.

I believe if you do this: by changing the values of something already inside game and test it yourself you will have the answer of your problem.

Yeah thank you very much for the proof of concept I need to find the naughty mod doing this... (spoiler : could be one of mine xD)

Could be. This is typically one the more easier things in mods to add. So I dont see any hinderance unless something is drastically changing stuff.

Hey,
The mod V1 is done and published, thank you again Gladen for your help !
You can check it here if you want :
https://steamhost.cn/steamcommunity_com/sharedfiles/filedetails/?id=2814208650
So to cut things short, I simply recreated files and it worked. I do believe the issue was generated by the following :
- At some point I did load a package which was already loaded in the mod, and when I tried to remove it (thinking it would only remove the duplicate) it did also generate some weird errors. I closed and reopened the package editor, and my files originally created in the first package were still here "apparently" but I strongly believe that they were actually erased when I removed the duplicate package.

Glad you could make it. :) Some over insane buffs to Bountiful melons sounds fun :D