Midi and Mono mix [Need Help]

I am using Tascam US-600 with cubase LE 5

I have 2 issues :

First I dont understand how to hear the midi track thought my Tascam US-600 with the mono guitar track .

Second when I Export Mix I only hear the Mono track.

Basicly it looks like the midi track is not considered by my tascam US-600 because when I click PLAY the guitar is playing thought my phone pluged into my Tascam and the Midi is playing thought my computer speakers .

I tried to change these (see image under) option but I didnt fixed the problem .

Thanks

If AI has (Devices-VST Instruments), load above mentioned VSTi there and select as output on MIDI track. If not, add Instrument track routed to HSSE or HalionOne (depending on version), move MIDI event to that track.

Thanks for the reply .

But maybe I didnt understand or do what you explained or it dosent work .

Anyone has the solution ?

Thanks