I want to use the microkorg sounds but use an oxygen midi controller because I need bigger keys/more octaves. Is this possible? (I don't have the microkorg yet, otherwise I'd just figure it out) thanks
According to this SoS Review, the MicroKorg has MIDI in/out/thru, which makes it very likely that it will work as a sound module just like the MS2000 series did.
If you don't yet have a MicroKorg, you might consider getting a MS2000r instead - it has a much better control panel and essentially the same sound engine. Prices may be lower since it lacks the tiny keyboard. I can confirm from personal experience that the MS2000r works great with a separate controller keyboard.