Yeah, the "drag n drop" feature doesn't work with this app
As far as you not "seeing" your file when you try to add a title...
When you click on "Add Title" and then navigate to the folder where you have saved your video, if you are not seeing it, there might be a couple reasons. What is the extension of your file? Is it mpg, mpeg, mpv, m1v, m2v, or vob? If this part is missing at the end of your file, it will not "see" it and then all you need to do is add .mpg to the end of the file name.
OR, when you have the "Add Title" window selected where you navigate to your folder, immediately to the right of where it says
file name:
click there and enter
*.*
That command will show you EVERYTHING in the folder and then you should be able to add the file, even if it's missing the extension.
IF, for some reason, it gives you an error when you are trying to add the file, please tell me what it says and we'll take it from there.
I realize that some of this might be frustrating, but don't be discouraged as we ALL had to learn how to do this stuff at some point and some of the process is "trial and error."