It is the same texture as the walls/StaticMeshes. It moves with you, it appears when you enter the room/corridor (the BSP is Hollow btw and not a normal brush) and disappears as soon as you reach the doorway.
It's a UT3 Texture I added to my Texture file in UT2004.
I took it and re-did it.. put it back in photoshop, (.tga etc and imported it, kept it as 512/512 and made it DXT_1) ..because I didn't want the shine from the original texture I wanted it in a flat finish.
It works fine on other maps, like with any custom Texture.
When I changed the textures in that corridor to a stock texture or even remove the Staticmeshes the white texture still stays there in that corridor.. nowhere else even if I haven't zoned it.
It's like a ghost and appears only in that corridor.
I thought it might of been the Powertube(s) texture difference so I took all collision off them and used a Blocking BSP to no avail.
Surface properties are I used Planar to align the textures and used middlemouse to enlarge the texture. I have other corridors exactly the same and have no problem with them.
Your right about the BSP problem because now in certain areas the map stutters.
I completely removed that corridor and adding another with different textures from stratch but the texture still appears there in that space.
I eventually completely removed that certain texture from my Texture file to see if that would remove this "ghost" texture...deleted the corridor and such but no.. after that a plain transparent white texture appears.
It's so annoying as the level was finished. All I had done was was re-align a couple of StaticMeshes in another zone to pretty them up a bit.. Built it, played it and bingo...that ghost texture. I might have to re-do the level from one of my auto-saves before this problem arose.