At the bottom of the most recent log I uploaded it showed as not being able to connect with hitbox.
Fortunately, streaming seems to be working in Studio now--I re-copied/pasted the stream key, which I had done at least a dozen times before, and now it's working. Don't know why it wasn't earlier. I'm just glad it's working now.
The frame-skipping thing seems to be mostly solved, though I'm using the "large file size" option the most now. I shouldn't worry about file size, as I have a fast internet connection.
Thanks for you help.