No sound on midi track

Hello evereyone ,
I’m working with cubase now for a few weeks, so I,m not yet realy familiar with it. I’m using Cubase LE6 with a Zoom R16 interface.
Now I’m working on a project where I’m creating a orchestra with virtual instruments, what I program in the key editor because I cannnot play a keyboard, and I don’'t have one. So I need a lot of instrument tracks, but I can inly use 8. So I was thinking I can use midi tracks for it. But I don’t no exactly how to set up that. I’ve red the manual many, manyu times, but that’s a lot difficult. I will understand English but in the manual they go realy fast and use a lot of technical terms so I don’t realy get the point.
When I set up a midi track, I create one. Than I go the midi device manager where I have to install an instrument and than there’s a mysterous story about patch banks, channels and programs???
So at a moment was getting sound of some notes drew in an event, but I only could send the midi to mcirosoft wavetable so the sound came out of my computer and not of the system.
Is there someone who can help me out with that… In clear words for a simple dutch guy like me??
And is it maybe a better option to upgrade to a version where I can use more instrument tracks, because they work realy easy?

MIDI tracks are strictly to trigger external kit in LE. Only Instrument tracks support VSTi’s.

OK, that’s clear, thanx a lot!! So I better could upgrade now?

Or render the inst tracks to audio and export the MIDI if further editing is required, freeing up inst tracks.