Avast on x64

So Im using Avast to have a look at it.

1. How do I purge the contents of the VRDB?

2. Im dissapointed to see that the processes of Avast are mostly 32 bit and are therefore being thunked down by wow64. This is slow and inefficient. They said it supports 64bit but it doesnt really at a kernel level.

Cheers