Transparency with T21s cause black LODs to show

[SimCity4IE 203]

 I added tubes via t21, and I keep getting this issue with the sc4model, and pretty much anything I try with t21s.

Would anyone know a solution? 

[SC4BOY 21]

That is a long reported issue with all transparent textures. I doubt you will find an answer. In most cases it can be made to go away temporarily by switching to underground view and then back, but it almost always returns. This is a major reason many folk are reluctant to model with transparent base textures. I think cogeo has some experience with "glass simulation" in models as you can see from his transit stations.. perhaps you might PM him (and take a look at some of his station models) to see if he has any suggestions.