1) Scrolling textures don't require any special image creation other than a simple filename change. The scrolling texture needs to have "scroll" (in lowercase!) in the first part of the filename (but be sure not to exceed the 15-character filename limit). The image scrolls from left to right so keep this in mind during creation and addition of motion blur if needed. Create your texture as you did in Part1. Save the bmp with the scroll name like so.
2) Apply the new scrolling texture to a func_conveyor. Set the world direction of the conveyor movement and then go into the texture edit mode and select your face. Look at the XYZ icon and see that the yellow leg of it is the direction of the texture scroll; it is also important for this direction to match the yaw of the func_conveyor entity for push direction. In the properties you can set the speed.
3) Compile the map and observe:
4) For if you want just an effect without the push, go into the properties and uncheck the "push" flag, and if you want the brush passable uncheck solid:
5) For a rushing water effect, apply a scrolling water texture select the func_conveyor and set the rendermode to additive & FX amount to "255". This can also be used for rain or various scifi effects: