What scook was trying to convey, I think, is that even though you can set up Dim Pro to use up to 4 different sounds (Elements, in Dim Pro terminology - I think), the synth itself only seems to have one stereo output.
This would mean then that you could not route the audio output from those sounds to separate audio tracks and all the sounds would be played together through a single audio track.
What most folks seem to do is to have separate instances of Dim Pro for each sound, so one instance loads only a single sound.
It is nowhere near as capable as something like Kontakt, from Native Instruments, which is a top of the line 3rd-party sampler.
I hope I have helped, and not gotten anything wrong - I always use separate instances for different sounds in Dim Pro, so the issue never really comes up for me.
A true multi-timbral synth, like Kontakt or even Cakewalk's TTS-1, both allow multiple loaded instruments, which can share a common midi channel or can each play on their own midi channel, and can have multiple audio outputs.
I believe TTS-1 has a smaller number of audio outputs than the 16 sounds and midi channels it works with - but I also don't use TTS-1 too often, so you would have to check that out. But it CAN certainly at least play 4, and maybe more, at the same time. Kontakt can have a BUNCH of audio outputs, but there are some glitches that result in (for me anyway) a max of about 6 or 7 loaded instruments going to 6-7 pairs of stereo audio outputs.
Anyways, the only issue with loading multiple instances of Dim Pro would be the memory required for each of the instances of it, but if you have 8 GB or more of memory and don't see a lot of memory issues, this might not ever cause you any extra work (freezing stuff to free up memory, etc).
Bob Bone