I asked a question about SystemModeler which is Wolfram's modeling tool and comes tightly integrated with Mathematica, yet I got people saying this was OT. Are SystemModeler questions alright? I would note that there is a system-modeler tag, so I assumed I could ask a question about SystemModeler if there was a tag for it.
I think the real question here is whether there is enough expertise and interest in SystemModeler among the participants of this site. I, personally, have neither the expertise nor the interest, so I would vote to keep SystemModeler questions off the site. But that's a sample of one. If enough participants come forward here and indicate an opposing position, I would be willing to vote to reopen your question.
To make my position completely clear: I think admitting SystemModeler question would spread us out too thin. I believe we already spread very thin just covering the questions we already get. I would emphasize that this just my opinion and that I could belong to a very small minority (maybe me alone).