[Fyron]

Missing AI files will be imported from the SE4\Pictures\Races\Racename folder before the Modname\AI folder will come into consideration. Modname\AI is only used if the stock Racename folder is also missing the AI files (or it doesn't exist in the first place).

If you do not have a Vorlon or Shadows set installed in your stock folder, and never, ever plan to, then deleting their AI Research files from the B5 Mod folders will work. But if you have these shipsets installed, you will create a new set of problems created by stock AI Research files being used in the B5 Mod.

Thus, for a complete solution you want to have a Vorlon_AI_Research.txt file in the B5 Mod folder that has nothing between the BEGIN and END blocks. This is the only surefire way to make sure they won't research anything non-existent.