I have CPA 9 and an ensoniq zr-76 board....
By "board," you mean a PC soundcard?
Well I want to record using other sounds from some of the instrument definitions that came with the software. How do I assign those sounds to work with my board.
You can't. Instrument definitions are
not sounds. They are just lists, mappings for Cakewalk to know what patchnames are at what program location, so that if you have a given synthesizer, you can more easily work with it. For example, if you had
a Roland JV-2080 synth, you would use the appropriate Cakewalk instrument definition file, and be able to select patches by name from those available -- but only if you actually have the physical Roland JV-2080 sitting there with MIDI cables connecting it to your PC.
Your board (again I'm assuming its a PC soundcard) probably has a GM synth, so it would use the GM instrument definition, and that's all the MIDI sounds you have, unless you have external sound sources or some kind of software sampler or synthesizer like GigaSampler or Rebirth, etc.