Started a K2, SE playthrough, got to nuke research, tried it on the first (20 t), crashed and got this. Any ideas?

The mod True Nukes (0.3.9) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event True-Nukes::on_script_trigger_effect (ID 154)
Unknown tile name: nuclear-high
stack traceback:
[C]: in function 'set_tiles'
True-Nukes/scripts/crater-system.lua:248: in function 'nukeTileChangesHeightAware'
True-Nukes/control.lua:281: in function 'atomic_weapon_hit'
True-Nukes/control.lua:398: in function <True-Nukes/control.lua:363>

LE: I also used the ruins mod, and found 2 nukes (20 t); I did a test just now with one and:

The mod True Nukes (0.3.9) caused a non-recoverable error.
Please report this error to the mod author.

Error while running event True-Nukes::on_script_trigger_effect (ID 154)
Unknown tile name: nuclear-high
stack traceback:
[C]: in function 'set_tiles'
True-Nukes/scripts/crater-system.lua:270: in function 'nukeTileChangesHeightAware'
True-Nukes/control.lua:281: in function 'atomic_weapon_hit'
True-Nukes/control.lua:398: in function <True-Nukes/control.lua:363>

Hi, do you have any other mods installed?
Particularly any tile heavy mods like dectorio or asphalt roads?

Yes, I do have dectorio.
Yup, disabled it and now it works ... good thing I didn't start to use its assets.
Thank you.

Yeah, you don't necessarily have to disable it, but you will need to reduce the number of tiles it generates, as factorio has a 255 limit on number of tiles.
Alien biomes has options to reduce the tile usage, so maybe try that as well... (Remove Obsolete Tiles maybe?)

Yes, tried that too and it worked (Remove Obsolete Tiles from alien biomes) ... noticed my walls were gone (being Dectorio probably) and I was ass naked LOL

Ah, interesting, hope you work that one out lol.