MeGui muxed output not correct

[mod]

Hi all. I've searched but I haven't found about this issue in the forum:
In the last 2 days I've made my first 2 DVD->XviD encodes with MeGui, and in both cases the muxed video+audio output file was corrupted.
I'm sorry I cannot post the log. In the img you can see that the filesize of the muxed output is wrong (691), while the one muxed with VDubMod is ok (719).

http://img104.imageshack.us/img104/1315/post8xn.png

Decoding the file muxed with MeGui is possible with VLC, but the video isn't decoded in the right way. I don't know how to say in english, let's say that until all the areas of the picture are "refreshed" by motion, all I can see are wrong color blocks:

http://img104.imageshack.us/img104/3669/vlcsnap2178983ra.jpg

Check GSpot:

http://img57.imageshack.us/img57/1328/mm2wy.th.jpg (http://img57.imageshack.us/img57/1328/mm2wy.jpg)

http://img57.imageshack.us/img57/9333/td2ti.th.jpg (http://img57.imageshack.us/img57/9333/td2ti.jpg)

The file muxed with VDM plays perfectly. I think there could be something wrong in my settings, but it seems strange to me that simply muxing can cause this.. help me please :)

I used latest MeGui with all updates.

If this has already been discussed somewhere else here, just redirect me to the correct page, thanks!