COBRA is a little unique compared to other firing systems as individual cues are connected to the module ground and are switched to connect to a shared set of positive pins. If you are designing a custom integration, this is no problem, however, the polarity may be reversed from what you are used to. Since igniters are not sensitive to polarity, this should not be a concern when firing fireworks.
The pin-outs on the 36S CEN50 port are:
Pins 1-36 are cues 1-36 (ground)
Pins 37-45 are empty
Pins 47-50 are shared positive