Well after some testing here are my conclusions:
1. There is in fact some limitating factor concerning file size (destination). I believe it has to do either with WavDest filter or File Writer filter.
1.1. My solution was to split the source WAV into 2 and run them through graphedit separately. Then join them back toghether. Worked perfectly.
2. The resultant 6ch wav, when I run it through besweet to create the AC3, channels get swapped in some manner. But if I use the same besweet to separate the 6ch wav into 6 mono wav files, they come out correctly (filenames that is - C, LR, LF etc).
2.2 My solution is to use the tool on this
thread by Amnon82, to use those six wav in the correct order, to mux them and create the new ac3!
Hope my experiences help someone. If there are simpler solutions please feel free to post
Regards,
Antonio
BTW: Found
this great 6ch (wav and wma) on MS's site to test channels. It might be useful to most of us!