First of all I want to say that OpenMx has been quite straightforward to start using given the documentation on this website.
I am interested in being able to use the score function directly and wonder whether this is feasible in OpenMx. For example, I might want to fit a unidimensional CFA and then to plug subject 23's data and the parameter estimates into the score function. One application of this is to examine the sensitivity of a result. I might want to plug in several different values for the estimate of, say, the factor variance while holding the other parameter estimates constant. A similar thing might be done with the information function.
That said, I realize that the optimization is being done numerically and not analytically. So I'm not sure whether "saving" the score or information function for a given model is straightforward to do.