Thank you, Andreas. I used Sony Vegas Pro 10.0. I like it a lot and really only touched on a tiny fraction of all the features it has and can do.
I have read a bit about that program on the internet and I have to say, it seems very professional, I think, it´s comparable with Adobe Premiere Pro. So, have my congratulations to that splendid program. I have read, one can also edit 3d-videos with it. That´s very interesting for me, because I have purchased a 3d-camera. (But the whole technic still is in the beginning of its development.)
I think I've got both parts synced up pretty well - it was hard because I did have to manipulate some tempos in certain sections and things like that. And every time I changed one thing, another thing down the road also changed. I feel like I could spend all eternity editing these and not ever be completely satisfied. Oh well...life goes on....I haven't touched my piano in over a week because I was working all the time on this project.
As I said you have done a pretty good job here. But the audio-files are not perfectly synchronized at some places. For this, I think, you will need a special audio-editing-program, in which you can overlay the two audio-tracks and correct the accord of some chords and tones of both tracks together. That´s what I do with the audio-montage-function of WaveLab. After you have synchronized the two audio-files you should synchronize the new track (the result of the two synchronized audio-files) with the videos. But the first step has always to be the synchronization of the only audio-files.
Btw, I don´t suppose, that YouTube has falsified the synchronization (though this can´t be absolutely excluded). In earlier times I also thought that sometimes, but later I found out, that the (more or less) bad synchronization in these cases was my own fault.
But aren't these two sweet little pieces?
Yes, these pieces are nice, not too deep, but entertaining in the best sense of that word.