In the Open-source microscopic traffic simulation models project, a component based software framework is proposed to re-engineer CORISM data struture and CORISM interface. Under the architecture combing the innovative framework and the legacy CORISM, prototype of the open source traffic flow simulation models will be developed and demonstrated in the Phase I. In addition, areas identified by the DOT SBIR 081-FH5 solicitation needs improvement or documentation will be enhanced or modeled. With the enhancement, the new traffic simulation will be used in DOT's VII, driving simulator and integrated corridor management research. The areas idetified includes the variable time steps, highway rail grade crossing safety models, Run Time Extension documentation, OD models in surface street, compiling CORISM in Linux and interfacing with other traffic simulation software like Texas models, DynaMIT, NGSIM etc.