I have http://i.imgur.com/hPV7hyS.jpg in Firewatch. This is the first time my char visits areas from Tamriel Rebuilt, so not sure if there are similar issues in other places. I am using Tamriel Rebuilt 14.08 and the bsa is registered in the ini. I searched the Nexus release thread for similar issues, but didn't find anything. What might cause this issue?

We just talked about the possible cause, mods or saved games created with a previous version of TR_Mainland.esm as master and not processed with Mash updaters.

But I've been using the very same version of TR the whole time, so it shouldn't be the save game issue in my case. Also, if I have a yellow plugin, I always use Wrye Mash's Master Update on it, so all plugins have been green. I tried without the UL TR plugin, but still the same issue.

EDIT: I checked all plugins that have TR_Mainland.esm as a master and I found it: it was abotWindowsGlowTR.esp. If I remove it, the issue is gone.

EDIT 2: Turned out that I was using abotWindowsGlow110 and updating it to WindowsGlowExpansion1dot11 fixed it. Thanks for pointing me in the right direction, i.e. checking plugins that have TR_Mainland.esm as a master.

I've got exactly the same problem than you (same walls missing). And I also use WindowGlow. If you go in Bal Oyra, you will also see problems on walls between sea and the town. But I had this when I installed latest version of TR_Mainland. When I play with former version, I haven't got this issue too. Maybe a little incompability between latest windowGlow mod and latest TR_Mainland ?

I have only tried with the latest TR release. In my case it was fixed by updating Windows Glow from 1.10 to 1.11. At least the walls in Firewatch - I haven't gone further yet.

Ah ok! I don't remember if I have v1.11 of Window Glow. I have v1.10. I try it now thanks.

EDIT : It works well now. Thanks!