Travis,
Jing requires Windows XP/Vista, Microsoft .Net Framework 3.0 (Mac OS X 10.4.9 or later); 8MB hard disk space; broadband recommended. Is it possible your computer can't handle the processing speed necessary to properly complete the screencast. I created mine on my laptop with is a Pentium 4, 2.8 MHz, 1 GB of memory. I still found creating the screencast to be jumpy, but overall it worked fine.
I did notice I had a problem embedding the screencast. When I copy and pasted all I got was the code. Instead I just pasted in the actual link, and that seems to work better. I'm sure with a little more patience I could of got the code to work, but at that time just using the URL was way easier.
I don't know if this helps. As a Jing newbie, I don't know much. All I can offer is the kind of computer that I created mine on and that I didn't have any real issues at all. Hopefully this can give you a base to start on.
Good luck.
Todd
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