The "modules" research is unavailable when AAI Industries is installed because:

1. AAI Industries makes the "modules" research require the "electric-lab" research from AAI Industries at: aai-industry_0.3.5/prototypes/technology/technology-update.lua:7:util.tech_add_prerequisites("modules", "electric-lab")
2. This technology is only used as a pre-req for "modules" and it unlocks the "lab" entity (without the items needed to construct it by SCT, so that should probably be removed and electromagnetism technology should depend on electric-lab anyway, or something like that).
3. SCT (this mod) then disables the "electric-lab" technology at:

ScienceCostTweakerM_0.17.7/tweaks/aai/1_update.lua:62:  if data.raw.technology["electric-lab"] then
ScienceCostTweakerM_0.17.7/tweaks/aai/1_update.lua:63:          data.raw.technology["electric-lab"].enabled = false

Interestingly in that same file are the same lines commented out at:

ScienceCostTweakerM_0.17.7/tweaks/aai/1_update.lua:20:--        if data.raw.technology["electric-lab"] then
ScienceCostTweakerM_0.17.7/tweaks/aai/1_update.lua:21:--                data.raw.technology["electric-lab"].enabled = false

Also, elsewhere in the file it actually adjusts the "electric-lab" tech to "SCT-ify" it. I'm guessing that when that was done the lines to disable that research was commented out without actually knowing that the same lines exist again later down in the file.

Without having tested it I'd guess that commenting out (or better yet, outright remove since git is used anywaythe above referenced lines (and theendline of course) would probably fix it and gate it behind the"electric-lab"` (that is already edited by SCT anyway) properly?

If anything I'd say that the "electric-lab" research should be left enabled and a few other research/lab related technologies should be attached to it too, specifically the electromagnetism lab research should require it and the 'lab' that it enables should be not enabled by it (since the electromagnetism lab technology by SCT enables it too along with the items required to build it). Either that or the technology should be left disabled and modules should not require it. :-)

Actually it seems that the electric lab requires a multitude of red research, which is fine, except the electromagnetism lab research unlocks 'those' researches, so they can't depend on each other. Perhaps if AAI Industries is installed then red the electromagnetism lab should be unlocked by electric lab technology, and the red science ("Sacrificial Electromagnet") should be unlocked in the burner era without requiring the electromagnetism lab since you can put them in AAI Industries burner lab anyway?

guess your problem lies in your mod combination, if you run AAI industries only, there is only single rechnology, that depends on electric lab, and that is modules, there is no other dependency in AAI industries.

if you disable electric-lab, it will still allow you to research modules, because they are also dependent on electronics-2.

if you load SCT+AAI only, there is still no problem with electric-lab removal, because what i wrote above.

from what you saying, seems to me, you are using other mods that mess with technology tree.

perhaps, there might be problem, if you add sct to already running game, i can't attest for that, because that's situation, where many mods can have issues, and best you can do is force.reset_technology and redo research.

technology will be hidden from tree in 2 cases
1) technology is disabled (like i do with electric lab)
2) all and every technology prerequisite is disabled (is some mod disable electronics-2 and electric-lab, modules in aai will become unresearchable, but that is not case with SCT)

i will do only thing i can and that is to remove modules dependency on electric lab, but for other stuff, you need to figure it out within your mod combination.

as for your guess, why there exist commented out disabling of electric-lab, this is because there are mods, that disable t0 in aai, for those it did break lot of stuff, that's why i moved tested inside block, which test for burner-lab presence.
if burner lab doesn't exist, then electric-lab might not too, it's simple as that.

some screenshot of tech tree
https://imgur.com/a/coyRJg1

from what you saying, seems to me, you are using other mods that mess with technology tree.

Hmm, as far as I've seen, all early research was added by AAI industries and/or SCT...

perhaps, there might be problem, if you add sct to already running game, i can't attest for that, because that's situation, where many mods can have issues, and best you can do is force.reset_technology and redo research.

Fresh from the start, was a new server started a week ago with both.

i will do only thing i can and that is to remove modules dependency on electric lab, but for other stuff, you need to figure it out within your mod combination.

No other issues but just electric lab missing, the rest is just feature enhancements. Just removing the electric lab dependency from "modules" fixes that fine. :-)

some screenshot of tech tree
https://imgur.com/a/coyRJg1

In your modules - AAI + SCT screenshot:
https://i.imgur.com/SfidCLL.jpg
This is precisely what I see, but when I research electronics 2 that is listed as the only dependency for the "modules" research (that is right above the efficiency modules research that is selected in that screenshot) then the "modules" research stays red. When I printed out the list of the dependencies of the "modules" research in game (open the console, run something like /c game.player.print(game.get_player(0).team.technologies["modules"].dependencies or whatever it was) shows that it has 2 dependencies, one is the electronics 2, the other is the "electric-lab", which if I check it the .enabled value of it is false, thus making the modules technology unresearchable. So disabling electric-lab is fine, but also need to remove it as a dependency from any technologies that depend on it, of which there could be others if mod added, but no others on the server that do, just "modules", so leaving it enabled would be the most 'safe' (just removing the unlocks from it would be useful, etc... to fit into the tech tree better) but it wouldn't do a whole lot other than just be something to research to unlock "modules".

So given your screenshot above of the modules - AAI + SCT screenshot, did you try researching up to electronics 2 and seeing if modules becomes available or if it stays red, as it's not showing that anything is researched at all?

Yes i did research in sandbox and it was possible to research and use modules, i did add dependency removal to code just to make sure, some otter mods altering will not have issue.

Hi
i use your mod with bobs / angels + aai
and i had the same problem , now i have blue since but moduels are not possebil

i tryed to find the config above but i dindt found anything , i removed aai + memixer and reload it but i cant research it

https://imgur.com/a/hmTqtGF

if u need anything please let me know it

I had not played for some time, and didn’t have much time for factorio in general. I know bob added some more technology to steam phase, but since i have not seen that yet, i can’t confirrm if they are compatibile now or not.

Can’t tell, wheni have time to look at it. Probly somewhere at end of month.