RUMMss was written by staff from the Pearson Psychometrics Laboratory. The program was written to simulate data for our own research (e.g. Andrich, Marais and Humphry, 2016), and it has also been used as a teaching tool in UWA Rasch courses. The program is being used by colleagues internationally, in published research and as a teaching tool in an Advanced Rasch course at the Psychometric Laboratory for Health Sciences, University of Leeds, England.
RUMMss is written in VisualBasic. Since VisualBasic is not supported anymore, and doesn't run on Windows 7 and up, the program needs to be upgraded to another platform, perhaps VisualStudio 2012? There are also some possible enhancements to the program, but those don't necessarily have to be part of this project.
Andrich, D., Marais, I. and Humphry, S. (2016) Controlling guessing bias in the dichotomous Rasch model applied to a large scale, vertically equated testing program. Educational and Psychological Measurement, 76(3), 412-435.