Gatling scenario with step up and quick ramp down

SearchDailymotion.scala

package dailymotion

import io.gatling.core.Predef._
import io.gatling.http.Predef._
import io.gatling.http.Headers.Names._
import scala.concurrent.duration._
import bootstrap._
import assertions._

object SearchDailymotion {

  val topQueries = tsv("es-top.csv").circular
  val autocompleteQueries = tsv("es-autocomplete.csv").circular
  def scn(step: Int, duration: Int) = scenario(s"Search Dailymotion Scenario $step")
    .feed(csv("elasticsearch.csv").random)
    .during(duration seconds) {
      randomSwitch(
        70 -> feed(autocompleteQueries)
                .exec(http("Autocomplete request")
                    .post("${base}${complete}")
                    .header("Content-Type", "application/json")
                    .body(StringBody("${request}")))
                .pause(2 seconds, 10 seconds),
        30 -> feed(topQueries)
                .exec(http("Search request")
                    .post("${base}${query}")
                    .header("Content-Type", "application/json")
                    .body(StringBody("${request}")))
                .pause(10 seconds, 30 seconds))
    }
}

class SearchDailymotionSimulation extends Simulation {

  val httpProtocol = http
    .acceptHeader("text/json,application/json")
    .acceptEncodingHeader("gzip, deflate")
    .userAgentHeader("Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/29.0.1547.57 Safari/537.36")
    .disableFollowRedirect

  // Parameters for this test
  val rampTime = 10                     // seconds
  val rampHeight = 5                    // users
  val steadyTime = 20                   // seconds
  val numSteps = 10

  val params = 1 to numSteps map { i =>
    SearchDailymotion.scn(i, (numSteps - i + 3) * (rampTime+steadyTime))
                                  .inject(
                                    nothingFor((i-1) * (rampTime+steadyTime) seconds),
                                    ramp(rampHeight users) over (rampTime seconds),
                                    nothingFor(steadyTime seconds))
                                }
  setUp(scenario("Nothing").inject(nothingFor(1 seconds)),
        params:_*)
    .protocols(httpProtocol)
    .assertions(
      global.successfulRequests.percent.is(100),
      details("Search request").responseTime.max.lessThan(1000),
      details("Autocomplete request").responseTime.max.lessThan(200))
}

Hi, does this still work with Gatling 2.2.2?
I get following error at line 55

no `: _*' annotation allowed here
(such annotations are only allowed in arguments to *-parameters)