Sequencing a MIDI file for the first time - lost

Background:
I've never used a sequencer - I've always produced (hopefully until now) with VST and music notation programs.

Equipment:
Cakewalk Sonar X2
Kontakt 4 (Standalone)
A ready-made MIDI file with 18, separate instrument tracks (saved from a Finale 2012 .mus score)


Goal:
I want to record the MIDI file with my Native Instrument samples (assigning a Kontakt instrument to each midi track). I'm normally good with directions, it's just I can't find any tutorial to help me do what I want. I tried using FL Studio and after an hour or less I managed to get a sample from Kontakt loaded and playable with a keyboard (without the midi track).

I'm hoping for some dumbed-down instructions, as I'm severely confused. Including, if necessary, how to setup Sonar X2 to do such a thing in the first place.

Thanks a bunch, and sorry.

Welcome to the forum Chris.
 
You have used a sequencer before, but one that was more focused on presenting the music in staff view than in playingmixing/mastering it.  You should be able to export your notation program as a .mid file.  You should then be able to import this .mid file into an X2 project using the FILE->IMPORT->MIDI menu path.  This should result in your project having 18 seperate MIDI tracks (assuming that is what was in your notation program).
 
While this results in the MIDI being in X2, there are no sounds (synths) associated with the tracks when they are first imported.  To get the sounds you will need to insert synth(s) into the project.  So lets assume that there are synths in your Kontact install and that they are VSTi instruments.  If X2 has scanned the VSTi directories that these soft instruments are in then you can insert the synth (looks like an audio track once inserted).  You then need to set up the patch for the synth and direct one of the MIDI tracks that you previously imported from your notation project to send its output to the track with the synth.  Alternatively, you can use any of the Cakewalk synths.
 
The synth now will create the sound from the notes in the MIDI file.  The output from the synth then needs to be directed to an audio output.  This is generally a stereo bus which then sends the sound to your audio device and speakers.
 
So then, we import the midi track and send the output of the midi track to a synth which sends its audio out to a bus which sends its output to your soundcard which sends the sound to the speakers.
 
Once you have inserted the synth that you want for each of the midi tracks X2 should be able to play your project.  You can control the sound levels of the mix by adjusting the levels on each of the synth tracks.
 
Select all tracks and you can then export the project as an audio (.wav, .mp3, etc) and plau it directly.
 
Does this help a bit?
 
Glen