Right click and select object properties, turn on vertex channel display and select vertex alpha from the drop down menu. This method now supports vertex painting for the alpha channel, that never worked in rf1, in rf1 all vertex alpha blending had to be done manually by hand. In my test track is a blending test where I have used vertex paint modifier to paint the blend into the terrain., Then you can do nice things like blur the edges. [ED] you will only see a black shade in max, you have to export it to see the actual blend.
Aha, yes, I think I did forget to mention you need to use the "Blended *" shaders. I suppose these things happen when you don't get much sleep ... It's pretty much self-explanatory if you read the shader description. The vertex alpha controls the blend between the two texture stages. Worth mentioning is that these texture stages do not need to share the same values (mapping channel for instance). I'll update the document soon. Thanks for letting me know .
