MEGUI & X264 = Macroblocks

[Cunhambebe]

I'm a total newbie with MEGUI and X264, but I guess X264 options are not that different from XviD's. Anyway, I'm trying to backup an MPEG2 Source as MP4 using both MEGUI and X264 (the source has some macroblocking, but very hard to see). I'm currently using the following options:

PD-Xbox_HiRes at an average bitrate of 1,300: result = macroblocks on the part of the video shown right here (this is the original source "withouth the macroblocks", only to show where they appear):



If I use zones at a minimum quantizer of 8 for an average quantizer of 26 (same config. options above), I've got that part with no macroblocks at all (same for the final credits), but the overall quality is poor.

Keeping the zones as shown above and config. the quantizers to a min. of 10 and max. of 38, makes the overall quality a lot better, but that part showing the clods/midst will show the macroblocks once again. Besides, the file gets much bigger than that one rendered as XviD (if you want to check out, please download it down there, on my signature: Brazil).
Here are the other settings (avs script):

DGDecode_mpeg2source("C:\brazil_watercolor.d2v",cp u=4,info=3)
ColorMatrix(hints=true)
#deinterlace
#crop
Lanczos4Resize(704,528) # Lanczos4 (Sharp)
Convolution3D("movielq") # Heavy Noise

Questions:
Why can't I achieve the same quality/size as I have done using XviD?

If you've got a better script for AVS, please give me a hint. Help will be greatly appreciated/
Thanks.

[Cunhambebe]

Well, I've found a way:
I have used the Profile AE-Maxquality, bitrate at 1,400, inserting 2 zones at Q 8 (for the part shown above and the end credits - effect on the text "brazil"). I'll upload the file later so you can take a look and compare it to the same file rendered as XviD.
Cheers.

Edit: The MP4 file is already here.