These values are used by the UK Building Regulations Studio and they should not be edited for any reason. They are not used when you simulate your tbd file.
Metabolic Rate (W/p) - the number of Watts per person transferred to the zone as heat. The occupancy gains (sensible + latent) in W/m^2 divided by the metabolic rate (W/p) will give the specified people density for the zone in p/m^2.
DHW (l/d/m^2) - used to calculate the domestic hot water load (Part L2 and EPC only).
Outside Air (l/s/p) - used to determine the minimum fresh air requirement (Part L2 and EPC only).
Target Room Illuminance (lx) - used to determine the required illuminance level within the zone at which the lighting gain will be set to its minimum (Part L2 and EPC only).