Vaughn wrote: "On any flavor of Windows, it's nearly impossible to run without TSRs in the background. Which types can get captured in layers?"
Well, strictly speaking, "TSR" is a DOS concept. But perhaps it will help to explain, Vaughn, that SVS captures file system and registry writes into layers based on where the process tree was launched from. If the process tree was started by a program running from Layer X, then the writes go into Layer X. If the process tree was started by a program running from the base, then the writes go into the base. In this regard, it's irrelevant to SVS what kind of process it is (driver, service, system vs. user process, application -- whatever).