rectify that need here.

’s development leading up to the 1998 review had emphasized the UV, optical, and IR spectra of ionized gas. The simulations have been extended to fully molecular regions with predictions of the associated IR and radio emission since then. The code can handle a broad range of physical state, from predominantly molecular to fully ionized, a broad range of densities from the low density limit to roughly $10^{15} \pcc$, and temperatures ranging from the CMB to $10^{10} \K$.

In the present paper, we summarize the major advances in the code since F98. Most of this work has been documented in past papers, which we cite. In the interests of brevity we only give references to the relevant papers with a brief summary of the advances they document. We discuss some technical details about the code, its operation, and installation. We present several calculations that show the range of applicability of . These include the properties of the ionized, atomic, and molecular gas produced by the radiation field of an Active Galactic Nucleus (AGN) and a demonstration of the range of particle and radiation density that can be considered. We conclude with an outline of future development 