Ruins aren't rendering correctly

[AbduSharif]

There are those ruins from a Total Conversion mod that works well with the original OpenMW's shaders but are bugged with those shaders, their "ori" command output:

Content file: 1 [MA_RoK_Eng v0001.esm]
RefNum: 21135
RefID: ex_br_ruine
Memory address: 0x79e7aeaf10
Cell: Skalgrin Forest
Grid: 0 -12
Coordinates: 4284.05 -94596.2 1096.87
Model: meshes\ruine_test.NIF
(BSA: /storage/emulated/0/Morrowind/Data Files/marok.bsa)

Original shaders:

Those shaders:

The mod can be downloaded from here: https://www.moddb.com/mods/myar-aranath-rellict-of-kallidar

[AbduSharif]

The rocks and the landscape being different here between screenshots is because I switched textures and meshes for those at some point, they're not related to the ruins.

The "ori" output shows the mesh can be found in "marok.bsa" file.