My guess would be that the agent.Agent Stats.Resources.% CPU Utilization (Host) is reporting on the total system CPU Utilization while the agent.CPU.Utilization % (process) is the amount of the CPU allocated to the process.
So if we have 6 CPU (600% max) on the system and we have 0.25 of a CPU allocated to a process, if the process is only using 1% of it's allocation, (0.0025% of a CPU and only 0.000041666 of the total CPU allocation of the server, the system utilization would not show any change since it is less than half a percent (rounding up to 1 to report a value)