Just double checked in custom battle and the Great Feral Stegadon is completely ok and not showing any of the reported issues.
Considering that most of these units have their variantmeshdefinition files tied to vanilla files I'm inclined to think that the real culprit here is another mod, probably a reskin one.
And please, for future reference: when reporting an issue you should ALWAYS try to replicate and confirm said issue by testing ONLY the suspected mod without any other mods running at the time of the test.

great feral carno, bastilodon, troglodon have ok textures. But Help. Great feral Stegadon is in bad texture. Missing, colors random and suddenly invinsible.

Mhhh...that's a lil odd, you should had unlocked the unit after upgrading the Terradon building into the Ripperdactyl one.
Oh well, guess that it make more sense to have Terradons in the tier 1 building anyway, will push another update in a bit.

scavengers and bloodspitters are there now, but still no terradons in terradon building

Thanks for the bug report, I pushed an update to address those issues.
Since it's unclear to me if CA deprecated the Lizardmen Animal resource building chain, the Bloodsplitters and Scavenger units will be directly recruitable from the Lizardmen beasts building chain from now on.
As a "downside" you should expect the Lizardmen AI to recruit Scavenger units way more often since they are cheap to recruit and are now easily accessible.
The Terradon issue was most likely caused by a missing building_units_allowed_tables value and it should be fixed now.
If you are still having issues after the update please try to unsub and resub to force the mod's update in case Steam failed to apply the update properly.

Terradons, scavengers, and cold ones don't show up, there is no building to recruit them. I built the terradon as Hexaotl and I can only recruit the base game terradon riders.

Yes, as they are available for all of the major Lizardmen factions.
If you have troubles finding certain units you can always check where they are unlocked in the building browser.

Does Gor-Rok get them?

Possibly, other modders may have covered Feral Nauglir, no idea about that really.
Ironically, Feral Nauglir started as a standalone mod for Dark Elves back in Warhammer 2 but since the ratings were pretty low they were then merged into More Ferals for Lizardmen (Lizardmen variant) and Cold One Variants (Dark Elves variant).
I'll add MCT support with the next update of this mod but that's not really a solution since disabled unit cards will still pop up as grayed out in the building chains and in the recruitment tab.
Plus, is not really worth it to be subbed to a unit pack just for a unit anyway.

Odd question, but is there a standalone version for the Nauglir, or perhaps another mod that expressly includes only them?

ALSO: do NOT try to load an ongoing campaign save file you made before the hotfix.
Between the mods that still need to be fixed and the ones who had to make fixes that broke save files it's pretty much a lost cause.
Just start a new campaign in that case.

And if you are still getting CTD with only this mod enabled, then you either have corrupted files on your part or Steam didn't update this mod on your end properly, in that case unsubbing and resubbing should fix the isssue.
And don't try to run this mod along my The Zerg Collection Volume I: this mod is already integrated in that collection and the game will crash if you try that.

Everything is good here.
The hotfix manage to bork a few mods but this is NOT one of those.
For future reference: you might want to be sure of what you are saying before claiming that a mod cause a CTD by doing extensive testing with the suspected faulty mod.
I'm generally chill (even if I'm in a bad mood right now) but other modders might not be so kind with you.
And PLEASE be more specific when reporting an issue "causing a CTD" is the most generic and unhelpful thing you could say to any modder.
ALWAYS specify if the CTD is related to game start up, hovering on a unit card attribute or ability, custom battle or campaign.
Investigate your mod list better and find your real culprit.

Causing a CTD again.

Fixed, the crash was tied to the Greater Feral Bastiladon having a super old attribute that got removed with CA's update to SOC.

Currently causing a CTD, investigating about the issue.
Sorry about that.

I have a problem with the mod, i didn't find it earlier in my life. LOVE the mod

i think this mod was the one that added that Big mother trucker so thanks for saving my empire

Can you please create a reskin mod for the Saurian, without any decoration to make it more feral ! There was a mod like this in TWW and it has been a good success, thanks :)