Ok, I don't remember if the blur esc has the little plug or if you have to program it through the wires going to the servo. If it has the plug, you have to plug it directly into the esc, not into the servo plug. you don't even need a castle link. most people that have computers will have it. i was programing a mamba max last night through the servo plug, it would not work, i had to pull the esc out and use the plug directly into the esc. you do not need the little circuit board included with the esc if it has that plug, just plug the black cord directly into the esc.