Thanks for the reply. I know that we can trigger different keys from the keyboard. But, from what I can tell, if you don't create your internal sequence based on C, then the keyboard notes to trigger it don't have any relevance to the key you are composing in. So.... if I make a sequence in the MB with 4 E's in a row, and then trigger the sequence by playing an E, it will actually play 4 G#'s in a row. If I wanted to hear 4 E's, I'd have to play a C on the keyboard. I hope that makes sense.
What would really be nice, is if the Matrix Brute library editor let you edit the sequences on a computer (including pitches, and copy+paste for rows/sequence length).