Thanks for reporting this, I've been running some tests here and it would seem that something has changed since that knowledge base article was written. At this point I'm not sure it it's due to the new version of RailClone, V-Ray or CrossMap. We're runnning further tests to see if we can isolate the issue. In the meantime you can still use CrossMap but you will have to set it up in a similar way to Bercon Gradient or Multitexture by following these steps.
1. In RailClone, wire the segment to a Material node and set it to Randomise. The Range chosen will determine the number of variations.
3. Create a new material and apply a CrossMap texture. Change the Image Distribution mode to Per Material ID
I hope that helps, please let me know if you have any further questions.