Have you gone into tools/instrument and assigned the M1 from the instrument definitions? (If you don't see it, click import) If you do that and assign the M1 to the midi channels that you want it to be assigned to (all of them if it's your only synth for Cakewalk), then -in track view- click on the source box, if the M1 doesn't show in the source box, click on instruments and assign it, then yo can select which bank from the bank box, the patch from that bank , and the midi channel you want that patch assigned to.