i learned the most abt the openmpt workflow by chopping up breaks. check out the breakcore is not a good way to get laid sample pack if you need some sounds to chop. it's on the forum.
openmpt also has great vst support and you can discover a lot just by fiddling with your freeware synth of your choice.
also have fun manipulating samples with the instruments tab.
all in all just, do it. the openmpt wiki is a fantastic resource, so if you ever want to learn more abt the commands or what openmpt can and can't do read it. i refer back to it almost every project.
wiki.openmpt.org
but even after tinkering for a while and not getting it, i'd suggest just trying a conventional DAW. fl studio has an infinite fully featured demo. ableton has a 90 day one, reaper a 60 day one, acid pro a 30 day one. (you can also obtain older versions of acid pro through "alternative means" *wink* they work great. 7.0 is what i use)
but yea bottom line just bust out sum jamz