I've freed a slave Yellow-Scales in Aimrah Inn. Even after freeing him, he still gives me a greeting about "needing a key from Dilvene Gilmanil to go free".
I talked to Horrav Fillipian about "Aimrah". He asked if I was going there, and then told the entire story. After picking the dialog "Aimrah" again, it was the same dialog again.
I've found a cave called Soudi, and there's a dark hole leading to it. This type of door lacks collision, so I can pass through it (the other side of the door is shown in the screenshot)
In "Nirmeni Ieneth" dialog, if I choose to pay, she takes the money and gives the directions, but if I choose "Nirmeni Ieneth" dialog again, I get exactly the same conversation. Not sure if this is intended, but maybe it'd be a good idea to give an updated dialog here.
While the bard, Sirrus Nedyra starts explaining himself (after the vampire attack) in "helping a bard" topic, there's a typo - "naviety" instead of "naivety",
note: there are more T_De_SetVeloth_X_LighthouseT_01 static positions wrong, use the right clik/info in the construction set and check all the references
There's a copy of Boethiah's Walking Stick, a unique item from vanilla, floating under the floor in the cell Oran Plantation, Oran Manor: Servant's Quarters. It's close enough to the interior space that it's visible on the minimap with Thief's Moral Compass equipped.
Firewatch, Iron-grip's weapons has instances of tr_m1_fw_irongrip_iron, tr_m1_fw_irongrip_steel and tr_m1_fw_irongrip_silver which are no longer necessary due to the associated quest being removed. They are also scattered around Firewatch generally which souldn't be the case.