I'm a little confused. If you want to bitstream DTS-HD MA, you don't need the Arcsoft dll file. That's only for decoding DTS-HD MA. If you want to decode the audio, I've found that you should uncheck both DTS-HD and plain DTS (so that the core isn't bitstreamed either).
Also, what hardware are you running. Some video cards do not bitstream HD codecs e.g. ATi 2xxx, 3xxx and 4xxx series, as well as the nVidia 9xxx, 2xx and 3xx series plus selected 4xx and 5xx cards. If you're running one of them, you're only option is to decode, in which case see my first paragraph.