from the guide posted item 4:
"....Select all audio tracks you have created with BeSweet...."
using besweet don't loose general volume with 2ch AC3 like in 5.1 AC3
in the end of that thread still don't have final solution for this volume problem and they are using cooledit or seamless audio editors doing double audio conversions..it's not a good choice. have some others threads in doom9 audio forum with better solutions that you can apply in this situations!
in the end you got some hundreds Mbs for the video but loose great audio quality,don't seems a good choice digitall.doc.
Kdvd is for good results in audio and video, cos the kvcd notch matrix do the hard job and give extra compression without losses giving space to use good audio tracks.