Yes you can try to get a comp but not likely to get the Plat. They often will give you a challege as well to get status, just ask. I too have many CO DL an NW miles....no real way to combine that i KNow of and if there is a way you would lose lots of value. HOwever, they are redeemable on each other, so once you have enough for a free ticket on say DL, you can us the miles on NW.