Since disconnecting the MAF solved your problem, I did a little research I am going to say your misfire problems are related to the Twintake, specifically the MAF section of the piping. Seems other folks have had similar problems. My advice would be to sell it, they are popular and easy to sell. I am running a CTS K04 intake and price was around 260 at the time and it has worked flawlessly. Our cars are quite similar except for intake so it would be a very safe choice. The other option is the Neuspeed which is CARB approved but I don't know if you would have the same problems as Twintake but a little research of what other DM K04 folks are using successfully should tell you if Neuspeed is a safe choice. A number of folks have had to chase down intake related problems of this nature.