I have Movie Studio HD Platinum Ver 10.0 (Build 179) running under Win 7 Professional and I have come across what looks like a strange bug.
Say you create 2 Media Bins, the first with sufficient files to require 3 display columns and second requiring only 2 display columns. You select the first Media Bin and drag the slider at the bottom of the Project Media window all the way to right. You then switch to the second Media Bin and find that it is apparently empty. However you notice that the slider has remained at the far right, so you drag it to left which now displays the missing files.
Next consider the case where the first Media Bin has 2 display columns whilst the second has only one column. You again select the first Media Bin and drag the slider to the far right. You now select the second Media Bin and find that there is nothing there. Surely all you need to do is drag the slider to the left. Unfortunately the slider has now disappeared (presumably because there is only one column) so thereís no way you can get the files into view! What you have to do is go back to the first Media Bin, drag the slider to the left, and then go back to the second Media Bin.
OK, itís not a killer but it is annoying and the first time it happened to me it was a while before I worked out why my files kept apparently disappearing at random.