Need help with Music Creator drums

I am a fairly inexperienced user, but I would so appreciate somebody's kind help with this problem. I am using Music Creator 6. I am using a Roland RD-700 keyboard and a Dell Vostro laptop. The interface I am using is an Omni interface (little blue box). I have successfully made a few instrument tracks that play back through my amp and now I want to add a drum track by turning the keys of my Rd-700 into individual drum sounds that will play out my amp like the other instruments do. I have worked at this for hours and I cannot make it happen. I have tried inserting the TTS-1 Softsynth and it works, but it won't play out my amp. It plays when I use the keys on my keyboard but it comes out my laptop speakers and I cannot use it that way as there are delay issues there and it messes up my timing. Can I fix this or am I going to have to scrap this project? Thanks so much for your help.

Thank you for your reply. I checked the settings you suggested. Here is what I found. The driver mode I have been using is MME (32-bit) The output setting where all my other instrument have been functioning is USB Uno Midi Interface. I now loaded up the Cakewalk Sound Center and the drum is playing through my speakers correctly when I hit the keys on the keyboard. However, when I save the piece as a Midi file and play it back in Windows Media Player the drum beat is instead a piano note. UGH!! Am I getting anywhere? :)