So, I have an issue that I described in another issue in the MSDN forums before finding this category (https://social.msdn.microsoft.com/Forums/en-US/20a6d712-5d98-4973-800d-ba5da9f3aa38/perfview-unable-to-see-my-classic-events?forum=clr).
Basically we have a log of Classic events (currently instrumenting our codebase which for legacy reasons needs to run on Win XP for the moment until we have all the fancy benchmarking to prove that we'll run better until Win 8) and WPA 6.2 seems to correctly identify them as classic events and we can actually view the opcode for each event, and more. Basically right-clicking on the column header provides a lot of options to select and view for each event, but when attempting to view in WPA 6.3, there's nowhere near as many options. In fact I can't select the opcode at all, or any of the other useful bits of information. Also, the provider name in WPA 6.2 is prefixed with "Classic", but in 6.3 it is not.
What does this mean? Does WPA 6.3 just not understand classic events?