Since upgrading to 3.6 we have experienced the following problem a few times per day (although it has only been a few days since we upgraded).
All of the channels go busy (similar to the problem that we were having with a single script earlier).
The task manager shows the usage at close to 100%. The details reveal that each of the 5 VFP processes is grabbing all of the processing time.
Like the earlier problem, it can be resolved by closing and restarting FW. Since it is not limited to a single script, I'm not sure how to approach debugging.