In December last year, I reported a similar issue, but didn't have the time to continue debugging.
I am having consistent problems with NF on a Win 7 64b machine.
We use separate logins for myself (Admin), wife and 2 children.
NF is only supposed to be monitoring the 2 children's accounts.
I have been trying to debug why the CPU runs constantly at sufficiently high loading that the fan is always on high. While it reports 75-90% idle time, I note that NF.exe jobs for myself, my wife, and my daughter are each reporting a "PF Delta" of 4,000 or more page faults *per second*. Note that while my wife and daughter are currently logged in, I am the only active user (their logins are in the suspended state associated with the Win7 "Switch User" action).
Note that the total amount of CPU time used by the NF.exe jobs for each of us seems to be proportional to the amount of time since we have logged in. The computer was re-started about 24 hours ago, and it has used 3:20 for my wife (not monitored, re-booted computer and logged in first), 2:06 for my daughter (monitored), and 1:17 for me (not monitored, logged in about 2:30 ago). There is also a SYSTEM user NF.exe that has taken 4:14, has much more I/O, but doesn't seem to be page thrashing.
One final clue: it appears that there is some interaction with the WmiPrvSE.exe process, which is using a fair amount of CPU on an ongoing basis and has logged over 30 minutes of CPU time since the re-boot. The only other job with more than 10 mins of CPU time since the reboot is the SYSTEM user process for n360.exe at 12 minutes.
Please help! I hate wasting this much energy, but I want to keep my children safe!