"This report is written as a supplement to LAMS 2539. It is hoped that one will be able to read LAMS 2539, with emphasis on the fourth part (Memorandum N-4-79OU by 0. Farmer), with this memorandum to bridge the gaps and understand more about the model used and what the KIB Program can be used for. The system is defined by subsystems or subprograms: Thrust System, Heat Exchanger, Neutron Dynamics, Rod Actuator Dynamics, and Thermocouple Dynamics. The original Kiwi-B Flow System is included in the first part of LAMS 2539. This has been replaced by the newer system which includes a turbo-pump (per R, Bohl & E. Wheatley). This system will not be included here. Recommendations are made for improvement and more work in certain areas."