Excellent renderer! For such fine piece of software I was waiting for!
I have only one small suggestion. It would be great, if the number of lobes/taps of Lanczos could be chosen like in ffdshow. I know that many people will claim that ringing becomes visible, but this is only true with test patterns and not with low pass filtered movies, because ringing only occurs near the band limit. The advantage of 8 or 10 taps is a much better frequency response and visible less aliasing.
I will be really happy when DVD works with madVR.