The meshes associated with the window types T_Imp_SetMw_X_2Window_01, TR_X_Com_2Window_01.nif, does not have support for Glow in the Darkh. I think the reason could be that this was missing in Melchior Darkh's original patch for Tamriel Data.
Same as my other comment. GitD support doesn't happen magically. Someone has to copy over the appropriate files from MD's TR patch to the TR data folder and see what's missing from there.
The meshes associated with the window types T_Imp_SetMw_X_2Window_01, TR_X_Com_2Window_01.nif, does not have support for Glow in the Darkh. I think the reason could be that this was missing in Melchior Darkh's original patch for Tamriel Data.
Reported by jonado on the TR website.