hi greg,
i think i was the same for me. but i had a bug in my wiring too: i thought that "DP-out" on the max7219 was equivalent to "segment H" but it's actually before "Segment A".
the basics of the code is right. you might have to adapt it. i can post mine if you want, but i'd need to clean it up.
there is no problem with your matrix module. two-color modules are either "common cathode" or "common anode". they have 8+8+8=24 pins for 64 bicolor LEDs. if your module has 16 pins, it's only one color and perfect for the max7219, which can't do two colours anyway.
///kuk
@tomek
hej (potsdam?),
i don't think it will work. because (funny to say that) of the MATRIX.
i started on the wiring when i noticed that i would have to connect each segment-anode of the module to two different max7219. since they are not synchronized with their digit scanning, the output would be uncontrolled i guess.
you can just use one 4x8 portion of the display though. which isn't so cool.