There are lots of unknowns in terms of how Colonial computers work. It is also unknown exactly what role the CNP plays. Maybe it's a layer on top of lower level components.
We do however know that the main displays in Raptors and possibly Vipers (as the Blackbird is part Viper in origin) are multi-function. In Ressurection Ship part 1, Apollo and Starbuck bring up an instant messaging application on displays that normally show dradis screens. The main rear display on Raptors have also been used for various other stuff. I therefore suspect that there is some kind of OS that provides task switching and basic user interface functionality, kind of like the OS on pre-smartphones. Like on those phones, the OS and the applications might be tightly bundled, but I don't think its fully monolithic. The CNP could be such an application, but it could also be something else.